Search results for: mass of the space craft
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7059

Search results for: mass of the space craft

2979 Cerebrovascular Modeling: A Vessel Network Approach for Fluid Distribution

Authors: Karla E. Sanchez-Cazares, Kim H. Parker, Jennifer H. Tweedy

Abstract:

The purpose of this work is to develop a simple compartmental model of cerebral fluid balance including blood and cerebrospinal-fluid (CSF). At the first level the cerebral arteries and veins are modelled as bifurcating trees with constant scaling factors between generations which are connected through a homogeneous microcirculation. The arteries and veins are assumed to be non-rigid and the cross-sectional area, resistance and mean pressure in each generation are determined as a function of blood volume flow rate. From the mean pressure and further assumptions about the variation of wall permeability, the transmural fluid flux can be calculated. The results suggest the next level of modelling where the cerebral vasculature is divided into three compartments; the large arteries, the small arteries, the capillaries and the veins with effective compliances and permeabilities derived from the detailed vascular model. These vascular compartments are then linked to other compartments describing the different CSF spaces, the cerebral ventricles and the subarachnoid space. This compartmental model is used to calculate the distribution of fluid in the cranium. Known volumes and flows for normal conditions are used to determine reasonable parameters for the model, which can then be used to help understand pathological behaviour and suggest clinical interventions.

Keywords: cerebrovascular, compartmental model, CSF model, vascular network

Procedia PDF Downloads 269
2978 Design and Implementation of Remote Application Virtualization in Cloud Environments

Authors: Shuen-Tai Wang, Ying-Chuan Chen, Hsi-Ya Chang

Abstract:

Cloud computing is a paradigm of computing that shifts the way computing has been done in the past. The users can use cloud resources such as application software or storage space from the cloud without needing to own them. This paper is focused on solutions that are anticipated to introduce IaaS idea to build cloud base services and enable the individual remote user's applications in cloud environments, which appear as if they are running on the end user's local computer. The available features of application delivery solution have been developed based on our previous research on the virtualization technology to offer applications independent of location so that the users can work online, offline, anywhere, with appropriate device and at any time. This proposed effort has the potential to positively provide an efficient, resilience and elastic environment for cloud service. Users no longer need to burden the system managers and drastically reduces the overall cost of hardware and software licenses. Moreover, this flexible remote application virtualization service represents the next significant step to the mobile workplace, and it lets users access their applications remotely through cloud services anywhere. This is also made possible by the low administrative costs as well as relatively inexpensive end-user terminals and reduced energy expenses.

Keywords: cloud computing, IaaS, virtualization, application delivery

Procedia PDF Downloads 274
2977 Grief and Repenting: The Engaging Remembrance in Thomas Hardy’s ‘Poems of 1912-13’

Authors: Chih-Chun Tang

Abstract:

Nostalgia, to some people, may seem foolhardy in a way. However, nostalgia is a completely and intensely private but social, collective emotion. It has continuing consequence and outgrowth for our lives as social actions. It leads people to hunt and explore remembrance of persons and places of our past in an effort to confer meaning of persons and places of present. In the ‘Poems of 1912-13’ Thomas Hardy, a British poet, composed a series of poems after the unexpected death of his long-disaffected wife, Emma. The series interprets the cognitive and emotional concussion of Emma’s death on Hardy, concerning his mind and real visit to the landscape in Cornwall, England. Both spaces perform the author’s innermost in thought to his late wife and to the landscape. They present an apparent counterpart of the poet and his afflicted conscience. After Emma had died, Hardy carried her recollections alive by roaming about in the real visit and whimsical land (space) they once had drifted and meandered. This paper highlights the nostalgias and feds that seem endlessly to crop up.

Keywords: Thomas Hardy, remembrance, psychological, poems 1912-13, Fred Davis, nostalgia

Procedia PDF Downloads 267
2976 Electricity Services and COVID-19: Understanding the Role of Infrastructure Improvements and Institutional Innovations

Authors: Javed Younas

Abstract:

Fiscal challenges pervade the electricity sector in many developing countries. Low bill payment and high theft mean utility customers have little incentive to conserve. It also means electricity distribution companies have less to invest in infrastructure maintenance, modernization, and technical upgrades. The low-quality electricity services can result impair the economic benefits from connections to the electrical grid. We study the impacts of two interventions implemented in Karachi, Pakistan, with the goal of reducing distribution losses and increasing revenue recovery: infrastructure improvements that made illegal connections physically more difficult and institutional innovations designed to increase communities’ trust in and cooperation with the utility. Using differences in implementation timing across space, we estimate the interventions’ impacts before the COVID-19 pandemic and their role in mitigating the pandemic’s effects on electricity services. Results indicate that the infrastructure improvements reduced losses, as well as the electricity delivered to the distribution system, a proxy for a generation. The institutional innovations significantly impacted revenue recovery, but not losses in their initial months; however, the efforts mitigated the pandemic’s negative effect on the utility finances.

Keywords: electricity, infrastructure, losses, revenue recovery

Procedia PDF Downloads 191
2975 Pain Control by Ketamine in Combat Situation; Consideration and Outcomes

Authors: Mohammad Javad Behzadnia, Hamidreza Javadzadeh

Abstract:

Background: Pain management is essential to surmounting multi-injured people in an overcrowded emergency setting. Its role would be more apparent when the physician encounters a mass casualty in a war zone or even a military prehospital. Having sedative and analgesic properties, rapid onset and offset effects, and maintaining the cardiovascular and respiratory contain are the main reason for selecting Ketamine as a good choice in the war zone. Methods: In a prospective interventional study in a war zone, we have selected and followed two groups of casualties for pain management. All were men with an average age of 26.6±8 y/o and 27.5 ±7 y/o in A and B groups, respectively. Group A received only Ketamine and Group B received Ketamine and diazepam. Results: This study showed that all of the injured patients who received Ketamine had experienced some agitation, and they may finally need benzodiazepines for sedation, but in group B that received benzodiazepine before or simultaneous with Ketamine, the agitation was significantly reduced. (P Value ≤0.05) Conclusion: Various factors may affect pain score and perception; patients' culture, mental health, previous drug usage, and addiction could alter the pain score in similar situations. It seems that the significant agitation is due to catecholamine release in stressful Moments of the battlefield. Accordingly, this situation could be exacerbated due to ketamine properties. Nonetheless, as a good choice in the war zone, Ketamine is now recommended to combine with benzodiazepines for procedural sedation and analgesia (PSA).

Keywords: battlefield, ketamine, benzodiazepine, pain control

Procedia PDF Downloads 86
2974 Comparative Analysis of Dissimilarity Detection between Binary Images Based on Equivalency and Non-Equivalency of Image Inversion

Authors: Adnan A. Y. Mustafa

Abstract:

Image matching is a fundamental problem that arises frequently in many aspects of robot and computer vision. It can become a time-consuming process when matching images to a database consisting of hundreds of images, especially if the images are big. One approach to reducing the time complexity of the matching process is to reduce the search space in a pre-matching stage, by simply removing dissimilar images quickly. The Probabilistic Matching Model for Binary Images (PMMBI) showed that dissimilarity detection between binary images can be accomplished quickly by random pixel mapping and is size invariant. The model is based on the gamma binary similarity distance that recognizes an image and its inverse as containing the same scene and hence considers them to be the same image. However, in many applications, an image and its inverse are not treated as being the same but rather dissimilar. In this paper, we present a comparative analysis of dissimilarity detection between PMMBI based on the gamma binary similarity distance and a modified PMMBI model based on a similarity distance that does distinguish between an image and its inverse as being dissimilar.

Keywords: binary image, dissimilarity detection, probabilistic matching model for binary images, image mapping

Procedia PDF Downloads 148
2973 Effect of Twin Cavities on the Axially Loaded Pile in Clay

Authors: Ali A. Al-Jazaairry, Tahsin T. Sabbagh

Abstract:

Presence of cavities in soil predictably induces ground deformation and changes in soil stress, which might influence adjacent existing pile foundations, though the effect of twin cavities on a nearby pile needs to be understood. This research is an attempt to identify the behaviour of piles subjected to axial load and embedded in cavitied clayey soil. A series of finite element modelling were conducted to investigate the performance of piled foundation located in such soils. The validity of the numerical simulation was evaluated by comparing it with available field test and alternative analytical model. The study involved many parameters such as twin cavities size, depth, spacing between cavities, and eccentricity of cavities from the pile axis on the pile performance subjected to axial load. The study involved many cases; in each case, a critical value has been found in which cavities’ presence has shown minimum impact on the behaviour of pile. Load-displacement relationships of the affecting parameters on the pile behaviour were presented to provide helpful information for designing piled foundation situated near twin underground cavities. It was concluded that the presence of the cavities within the soil mass reduces the ultimate capacity of pile. This reduction differs according to the size and location of the cavity.

Keywords: axial load, clay, finite element, pile, twin cavities, ultimate capacity

Procedia PDF Downloads 229
2972 From Data Processing to Experimental Design and Back Again: A Parameter Identification Problem Based on FRAP Images

Authors: Stepan Papacek, Jiri Jablonsky, Radek Kana, Ctirad Matonoha, Stefan Kindermann

Abstract:

FRAP (Fluorescence Recovery After Photobleaching) is a widely used measurement technique to determine the mobility of fluorescent molecules within living cells. While the experimental setup and protocol for FRAP experiments are usually fixed, data processing part is still under development. In this paper, we formulate and solve the problem of data selection which enhances the processing of FRAP images. We introduce the concept of the irrelevant data set, i.e., the data which are almost not reducing the confidence interval of the estimated parameters and thus could be neglected. Based on sensitivity analysis, we both solve the problem of the optimal data space selection and we find specific conditions for optimizing an important experimental design factor, e.g., the radius of bleach spot. Finally, a theorem announcing less precision of the integrated data approach compared to the full data case is proven; i.e., we claim that the data set represented by the FRAP recovery curve lead to a larger confidence interval compared to the spatio-temporal (full) data.

Keywords: FRAP, inverse problem, parameter identification, sensitivity analysis, optimal experimental design

Procedia PDF Downloads 271
2971 A Comparative Study of Language Used in English Newspaper Dailies of Mumbai in Addressing Disability Related Issues

Authors: Amrin Moger, Martin Mathew, Sagar Bhalerao

Abstract:

Mass media may be categorized into print and digital, former being the traditional form of reaching the masses to inform and educate on various issues. The Indian print media is more than two centuries old. Its strengths have largely been shaped by its historical experience and, in particular, by its association with the freedom struggle as well as movements for social emancipation, reform, and amelioration. Therefore, it is highly regarded in the Indian society. Persons with disability are part of Indian Society. Persons with Disability have always been looked down upon and not considered as part of the society. People with disabilities were commonly feared, pitied, and neglected. Much of the literature on disability in India has pointed to the importance of the concept of karma in attitudes to disability, with disability perceived either as punishment for misdeeds in the past lives of the PWD, or the wrongdoings of their parents. Some Indian authors consider the passage of the PWD Act as a landmark step in the history of rehabilitation services in India have put it, ‘At a profoundly serious and spiritual level, disability represents divine justice’. The newspaper has to play a role where it changes this attitude of the people. A short comparative content analysis of two English newspapers of Mumbai edition was selected, to analyze the language that is used for reporting disability issues. Software Package for Social Science (SPSS) was used to gather and analyze data.

Keywords: content analysis, disability, newspaper dailies, language

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2970 A TFETI Domain Decompositon Solver for von Mises Elastoplasticity Model with Combination of Linear Isotropic-Kinematic Hardening

Authors: Martin Cermak, Stanislav Sysala

Abstract:

In this paper we present the efficient parallel implementation of elastoplastic problems based on the TFETI (Total Finite Element Tearing and Interconnecting) domain decomposition method. This approach allow us to use parallel solution and compute this nonlinear problem on the supercomputers and decrease the solution time and compute problems with millions of DOFs. In our approach we consider an associated elastoplastic model with the von Mises plastic criterion and the combination of linear isotropic-kinematic hardening law. This model is discretized by the implicit Euler method in time and by the finite element method in space. We consider the system of nonlinear equations with a strongly semismooth and strongly monotone operator. The semismooth Newton method is applied to solve this nonlinear system. Corresponding linearized problems arising in the Newton iterations are solved in parallel by the above mentioned TFETI. The implementation of this problem is realized in our in-house MatSol packages developed in MATLAB.

Keywords: isotropic-kinematic hardening, TFETI, domain decomposition, parallel solution

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2969 Survey of the Role of Contextualism in the Designing of Cultural Constructions Based on Rapoport Views

Authors: E. Zarei, M. Bazaei, A. Seifi, A. Keshavarzi

Abstract:

Amos Rapoport, based on his anthropology approach, believed that the space origins from the human body and influences on human body mutually. As a holistic approach in architecture, Contextualism describes a collection of views in philosophy which emphasize the context in which an action, utterance, or expression occurs, and argues that, in some important respect, the action, utterance, or expression can only be understood relative to that context. In this approach, the main goal – studying the role of cultural component in the Contextualism construction shaping up, based on Amos Rapoport’s anthropology approach- has being done by descriptive- analytic method. The results of the research indicate that in the field of Contextualism designing, referring to the cultural aspects are as necessary as the physical dimensions of a construction. Rapoport believes that the shape of a construction is influenced by cultural aspects and he suggests a kind of mutual interaction between human and environment that should be considered in housing. The mail goal of contextual architecture is to establish an interaction between environment, human and culture. According to this approach, a desirable design should be in harmony with this approach.

Keywords: Amos Rapoport, anthropology, contextual architecture, culture

Procedia PDF Downloads 391
2968 Themes in Aesthetic Perceptions of Restorative Urban Landscapes

Authors: Rachel Bechtold, Catherine Shoulders, Donald Johnson, Jennie Popp, Elena Garcia, Lisa Wood

Abstract:

Creating successfully restored urban landscapes involves both the sound design of natural resources and the incorporation of human perceptions of landscape. Moving forward with an invested interest from society is a challenge for the efficacy of reclaimed landscape design. In particular, urban areas present a dynamic environment wherein society and nature compete for resources and space. This review is meant to examine how perceptions of urban community members, the stakeholders for the plant species that share their environment, are reflected in aesthetic considerations. Findings from this literature review include themes of (1) aesthetic perceptions of stakeholders in rehabilitated landscapes and (2) the importance of organizing indicators of aesthetic perception for future design decisions. Recommendations include addressing the gap in research on aesthetic perceptions of reclaimed urban landscapes and addressing the lack of a consistent and widely accepted framework for these interdisciplinary studies. With knowledge of stakeholder perceptions, improved aesthetic and ecologic designs can more seamlessly merge into reclaimed urban landscapes.

Keywords: phytoremediation, urban landscape design, aesthetic perception, landscape ecology, phytorestoration, landscape reclamation, rehabilitation

Procedia PDF Downloads 188
2967 Quantitative Evaluation of Endogenous Reference Genes for ddPCR under Salt Stress Using a Moderate Halophile

Authors: Qinghua Xing, Noha M. Mesbah, Haisheng Wang, Jun Li, Baisuo Zhao

Abstract:

Droplet digital PCR (ddPCR) is being increasingly adopted for gene detection and quantification because of its higher sensitivity and specificity. According to previous observations and our lab data, it is essential to use endogenous reference genes (RGs) when investigating gene expression at the mRNA level under salt stress. This study aimed to select and validate suitable RGs for gene expression under salt stress using ddPCR. Six candidate RGs were selected based on the tandem mass tag (TMT)-labeled quantitative proteomics of Alkalicoccus halolimnae at four salinities. The expression stability of these candidate genes was evaluated using statistical algorithms (geNorm, NormFinder, BestKeeper and RefFinder). There was a small fluctuation in cycle threshold (Ct) value and copy number of the pdp gene. Its expression stability was ranked in the vanguard of all algorithms, and was the most suitable RG for quantification of expression by both qPCR and ddPCR of A. halolimnae under salt stress. Single RG pdp and RG combinations were used to normalize the expression of ectA, ectB, ectC, and ectD under four salinities. The present study constitutes the first systematic analysis of endogenous RG selection for halophiles responding to salt stress. This work provides a valuable theory and an approach reference of internal control identification for ddPCR-based stress response models.

Keywords: endogenous reference gene, salt stress, ddPCR, RT-qPCR, Alkalicoccus halolimnae

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2966 DesignChain: Automated Design of Products Featuring a Large Number of Variants

Authors: Lars Rödel, Jonas Krebs, Gregor Müller

Abstract:

The growing price pressure due to the increasing number of global suppliers, the growing individualization of products and ever-shorter delivery times are upcoming challenges in the industry. In this context, Mass Personalization stands for the individualized production of customer products in batch size 1 at the price of standardized products. The possibilities of digitalization and automation of technical order processing open up the opportunity for companies to significantly reduce their cost of complexity and lead times and thus enhance their competitiveness. Many companies already use a range of CAx tools and configuration solutions today. Often, the expert knowledge of employees is hidden in "knowledge silos" and is rarely networked across processes. DesignChain describes the automated digital process from the recording of individual customer requirements, through design and technical preparation, to production. Configurators offer the possibility of mapping variant-rich products within the Design Chain. This transformation of customer requirements into product features makes it possible to generate even complex CAD models, such as those for large-scale plants, on a rule-based basis. With the aid of an automated CAx chain, production-relevant documents are thus transferred digitally to production. This process, which can be fully automated, allows variants to always be generated on the basis of current version statuses.

Keywords: automation, design, CAD, CAx

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2965 From Vertigo to Verticality: An Example of Phenomenological Design in Architecture

Authors: E. Osorio Schmied

Abstract:

Architects commonly attempt a depiction of organic forms when their works are inspired by nature, regardless of the building site. Nevertheless it is also possible to try matching structures with natural scenery, by applying a phenomenological approach in terms of spatial operations, regarding perceptions from nature through architectural aspects such as protection, views, and orientation. This method acknowledges a relationship between place and space, where intentions towards tangible facts then become design statements. Although spaces resulting from such a process may present an effective response to the environment, they can also offer further outcomes beyond the realm of form. The hypothesis is that, in addition to recognising a bond between architecture and nature, it is also plausible to associate such perceptions with the inner ambient of buildings, by analysing features such as daylight. The case study of a single-family house in a rainforest near Valdivia, Chilean Patagonia is presented, with the intention of addressing the above notions through a discussion of the actual effects of inhabiting a place by way of a series of insights, including a revision of diagrams and photographs that assist in understanding the implications of this design practice. In addition, figures based on post-occupancy behaviour and daylighting performance relate both architectural and environmental issues to a decision-making process motivated by the observation of nature.

Keywords: architecture, design statements, nature, perception

Procedia PDF Downloads 338
2964 Investigation on a Wave-Powered Electrical Generator Consisted of a Geared Motor-Generator Housed by a Double-Cone Rolling on Concentric Circular Rails

Authors: Barenten Suciu

Abstract:

An electrical generator able to harness energy from the water waves and designed as a double-cone geared motor-generator (DCGMG), is proposed and theoretically investigated. Similar to a differential gear mechanism, used in the transmission system of the auto vehicle wheels, an angular speed differential is created between the cones rolling on two concentric circular rails. Water wave acting on the floating DCGMG produces and a gear-box amplifies the speed differential to gain sufficient torque for power generation. A model that allows computation of the speed differential, torque, and power of the DCGMG is suggested. Influence of various parameters, regarding the construction of the DCGMG, as well as the contact between the double-cone and rails, on the electro-mechanical output, is emphasized. Results obtained indicate that the generated electrical power can be increased by augmenting the mass of the double-cone, the span of the rails, the apex angle of the cones, the friction between cones and rails, the amplification factor of the gear-box, and the efficiency of the motor-generator. Such findings are useful to formulate a design methodology for the proposed wave-powered generator.

Keywords: amplification of angular speed differential, circular concentric rails, double-cone, wave-powered electrical generator

Procedia PDF Downloads 151
2963 A Dynamical Approach for Relating Energy Consumption to Hybrid Inventory Level in the Supply Chain

Authors: Benga Ebouele, Thomas Tengen

Abstract:

Due to long lead time, work in process (WIP) inventory can manifest within the supply chain of most manufacturing system. It implies that there are lesser finished good on hand and more in the process because the work remains in the factory too long and cannot be sold to either customers The supply chain of most manufacturing system is then considered as inefficient as it take so much time to produce the finished good. Time consumed in each operation of the supply chain has an associated energy costs. Such phenomena can be harmful for a hybrid inventory system because a lot of space to store these semi-finished goods may be needed and one is not sure about the final energy cost of producing, holding and delivering the good to customers. The principle that reduces waste of energy within the supply chain of most manufacturing firms should therefore be available to all inventory managers in pursuit of profitability. Decision making by inventory managers in this condition is a modeling process, whereby a dynamical approach is used to depict, examine, specify and even operationalize the relationship between energy consumption and hybrid inventory level. The relationship between energy consumption and inventory level is established, which indicates a poor level of control and hence a potential for energy savings.

Keywords: dynamic modelling, energy used, hybrid inventory, supply chain

Procedia PDF Downloads 259
2962 Effect of Channel Variation of Two-Dimensional Water Tunnel to Study Fluid Dynamics Phenomenon

Authors: Rizka Yunita, Mas Aji Rizki Wijayanto

Abstract:

Computational fluid dynamics (CFD) is the solution to explain how fluid dynamics behavior. In this work, we obtain the effect of channel width of two-dimensional fluid visualization. Using a horizontal water tunnel and flowing soap film, we got a visualization of continuous film that can be observe a graphical overview of the flow that occurs on a space or field in which the fluid flow. The horizontal water tunnel we used, divided into three parts, expansion area, parallel area that used to test the data, and contraction area. The width of channel is the boundary of parallel area with the originally width of 7.2 cm, and the variation of channel width we observed is about 1 cm and its times. To compute the velocity, vortex shedding, and other physical parameters of fluid, we used the cyclinder circular as an obstacle to create a von Karman vortex in fluid and analyzed that phenomenon by using Particle Imaging Velocimetry (PIV) method and comparing Reynolds number and Strouhal number from the visualization we got. More than width the channel, the film is more turbulent and have a separation zones that occurs of uncontinuous flowing fluid.

Keywords: flow visualization, width of channel, vortex, Reynolds number, Strouhal number

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2961 Blue Eyes and Blonde Hair in Mass Media: A News Discourse Analysis of Western Media on the News Coverage of Ukraine

Authors: Zahra Mehrabbeygi

Abstract:

This research is opted to analyze and survey discourse variety and news image-making in western media regarding the news coverage of the Russian army intrusion into Ukraine. This research will be done on the news coverage of Ukraine in a period from February 2022 to May 2022 in five western media, "BBC, CBS, NBC, Al Jazeera, and Telegraph." This research attempts to discover some facts about the news policies of the five western news agencies during the circumstances of the Ukraine-Russia war. Critical theories in the news, such as Framing, Media Imperialism of News, Image Making, Discourse, and Ideology, were applied to achieve this goal. The research methodology uses Van Dijk's discourse exploration method based on discourse analysis. The research's statistical population is related to all the news about racial discrimination during the mentioned period. After a statistical population survey with Targeted Sampling, the researcher randomly selected ten news cases for exploration. The research findings show that the western media have similarities in their texts via lexical items, polarization, citations, persons, and institutions. The research findings also imply pre-suppositions, connotations, and components of consensus agreement and underlying predicates in the outset, middle, and end events. The reaction of some western media not only shows their bewilderment but also exposes their prejudices rooted in racism.

Keywords: news discourse analysis, western media, racial discrimination, Ukraine-Russia war

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2960 Quantification of Polychlorinated Biphenyls (PCBs) in Soil Samples of Electrical Power Substations from Different Cities in Nigeria

Authors: Omasan Urhie Urhie, Adenipekun C. O, Eke W., Ogwu K., Erinle K. O

Abstract:

Polychlorinated Biphenyls (PCBs) are Persistent organic pollutants (POPs) that are very toxic; they possess ability to accumulate in soil and in human tissues hence resulting in health issues like birth defect, reproductive disorder and cancer. The air is polluted by PCBs through volatilization and dispersion; they also contaminate soil and sediments and are not easily degraded. Soil samples were collected from a depth of 0-15 cm from three substations (Warri, Ughelli and Ibadan) of Power Holding Company of Nigeria (PHCN) where old transformers were dumped in Nigeria. Extraction and cleanup of soil samples were conducted using Accelerated Solvent Extraction (ASE) with Pressurized Liquid extraction (PLE). The concentration of PCBs was determined using gsas chromatography/mass spectrometry (GC/MS). Mean total PCB concentrations in the soil samples increased in the order Ughelli ˂ Ibadan˂ Warri, 2.457757ppm Ughelli substation 4.198926ppm, for Ibadan substation and 14.05065ppm at Warri substation. In the Warri samples, PCB-167 was the most abundant at about 30% (4.28086ppm) followed by PCB-157 at about 20% (2.77871), of the total PCB concentrations (14.05065ppm). Of the total PCBs in the Ughelli and Ibadan samples, PCB-156 was the most abundant at about 44% and 40%, respectively. This study provides a baseline report on the presence of PCBs in the vicinity of abandoned electrical power facilities in different cities in Nigeria.

Keywords: polychlorintated biphenyls, persistent organic pollutants, soil, transformer

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2959 City on Fire: An Ethnography of Play and Politics in Johannesburg Nightclubs

Authors: Beth Vale

Abstract:

Academic research has often neglected the city after dark. Surprisingly little consideration has been given to the every night life of cities: the spatial tactics and creative insurgencies of urban residents when night falls. The focus on ‘pleasure’ in the nocturnal city has often negated the subtle politics of night-time play, embedded in expressions of identity, attachment and resistance. This paper investigates Johannesburg nightclubs as sites of quotidian political labour, through which young people contest social space and their place in it, thereby contributing to the city’s effective and socio-political cartography. The tactical remodelling of the nocturnal city through nightclubbing traces lines of desire (material, emotional, sexual), affiliation, and fear. These in turn map onto young people’s expressions of their social and political identities, as well as their attempts at place-making in a ‘post-apartheid’ context. By examining the micro-politics of the cities' nightclubs, this paper speaks back to an earlier post-94 literature, which regularly characterised Johannesburg youth as superficial, individualist and idealistic. Similarly, some might position nightclubs as sites of frivolous consumption or liberatory permissiveness. Yet because nightclub spaces are racialised, classed and gendered, historically-signified and socially regulated, they are also profoundly political. Through ordinary encounters on the cities' dancefloors, young Jo’burgers are imagining, contesting and negotiating their socio-political identities and indeed their claims to the city. Meanwhile, the politics of this generation of youth, who are increasingly critical of the utopian post-apartheid city, are being increasingly inserted and coopted into night-time cultures. Data for this study was gathered through five months of ethnographic fieldwork in Johannesburg nightclubs, including over 120 hours of participant observation and in-depth interviews with organisers and partygoers. Interviewees recognised that parties, rather than being simple frivolity, are a cacophony of celebration, mourning, worship, rage, rebellion and attachment. Countering standard associations between partying and escapism, party planners, venue owners and nightclub audiences were infusing night-time infrastructures with the aesthetics of politics and protest. Not unlike parties, local political assemblies so often rely on music, dance, the occupation of space, and a heaving crowd. References to social movements, militancy and anti-establishment emerged in nightclub themes, dress codes and décor. Metaphors of fire crossed over between party and protest, both of which could be described as having ‘been lit’ or having ‘brought flames’. More so, young people’s articulations of the city’s night-time geography, and their place in it, reflected articulations of race, class and ideological affiliation. The location, entrance fees and stylistic choices of one’s chosen club destination demarcated who was welcome, while also signalling membership to a particular politics (whether progressive or materialistic, inclusive or elitist, mainstream or counter-culture). Because of their ability to divide and unite, aggravate and titillate, mask and reveal, club cultures might offer a mirror to the complex socialities of a generation of Jo’burg youth, as they inhabit, and bring into being, a contemporary South African city.

Keywords: affect, Johannesburg, nightclub, nocturnal city, politics

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2958 The Effect of Ultrasound Pretreatment on Bioactive Compounds of Freeze-Dried Carrots

Authors: Gulcin Yildiz

Abstract:

Although drying is one of the most prevalent techniques applied to enhance food stability, it is a complicated method covering simultaneous coupled heat and mass transfer phenomena and the theoretical application of these phenomena to food products becomes challenging because of the complex structure and to the physical and chemical changes that happen at drying. Pretreatment of materials before drying has been shown to be effective in solving drying problems such as long drying times and poor product quality. The study was conducted to examine the effect of ultrasound (US) pre-treatment on physical and chemical/nutritional attributes of freeze-dried carrot slices. The carrots were washed, hand-peeled, and cut with dimensions of 1 cm (L) x 0.2 (W) cm x 1 cm (H). The carrot samples were treated in an ultrasonic bath in two different times, which were 15 and 30 minutes. Untreated and ultrasound pre-treated carrot samples were dried in a freeze dryer. Freeze-dried samples were analyzed in terms of bioactive compounds, including total phenols, ascorbic acid, and antioxidant capacity. Significant differences were found among dried carrot samples with and without ultrasound. The freeze-dried carrot slices treated with a US (especially 30 minutes - treatment) showed higher preservation of bioactive compounds. In overall, US pretreatment is a promising process, as demonstrated in current research by its capability to better retain freeze-dried carrot quality.

Keywords: bioactive compounds, carrot, freeze drying, ultrasound-pretreatment

Procedia PDF Downloads 109
2957 Biodegradation Study of a Biocomposite Material Based on Sunflower Oil and Alfa Fibers as Natural Resources

Authors: Sihem Kadem, Ratiba Irinislimane, Naima Belhaneche

Abstract:

The natural resistance to biodegradation of polymeric materials prepared from petroleum-based source and the management of their wastes in the environment are the driving forces to replace them by other biodegradable materials from renewable resources. For that, in this work new biocomposites materials have been synthesis from sunflower oil (Helianthus annuus) and alfa plants (Stipatenacissima) as natural based resources. The sunflower oil (SFO) was chemically modified via epoxidation then acrylation reactions to obtain acrylated epoxidized sunflower oil resin (AESFO). The AESFO resin was then copolymerized with styrene as co-monomer in the presence of boron trifluoride (BF3) as cationic initiator and cobalt octoate (Co) as catalyst. The alfa fibers were treated with alkali treatment (5% NaOH) before been used as bio-reinforcement. Biocomposites were prepared by mixing the resin with untreated and treated alfa fibers at different percentages. A biodegradation study was carried out for the synthesized biocomposites in a solid medium (burial in the soil) by evaluated, first, the loss of mass, the results obtained were reached between 7.8% and 11% during one year. Then an observation under an optical microscope was carried out, after one year of burial in the soil, microcracks, brown and black spots were appeared on the samples surface. This results shows that the synthesized biocomposites have a great aptitude for biodegradation.

Keywords: alfa fiber, biocomposite, biodegradation, soil, sunflower oil

Procedia PDF Downloads 156
2956 Analysis of Mechanisms for Design of Add-On Device to Assist in Stair Climbing of Wheelchairs

Authors: Manish Kumar Prajapat, Vishwajeet Sikchi

Abstract:

In the present scenario, many motorized stair climbing wheelchairs are available in the western countries which are significantly expensive and hence are not popular in developing countries. Also, such wheelchairs tend to be bulkier and heavy which makes their use for normal conditions difficult. Manually operated solutions are rarely explored in this space. Therefore, this project aims at developing a manually operated cost effective solution for the same. Differently abled people are not required to climb stairs frequently in their daily use. Because of this, carrying a stair climbing mechanism attached to the wheelchair permanently adds redundant weight to the wheelchair which reduces ease of use of the wheelchair. Hence, the idea of add-on device for stair climbing was envisaged wherein the wheelchair is mounted onto add-on only at the time when climbing the stairs is required. This work analyses in detail the mechanism for stair climbing of conventional wheelchair followed by analysis and iterations on multiple mechanisms to identify the most suitable mechanism for application in the add-on device. Further, this work imparts specific attention to optimize the force and time required for stair climbing of wheelchairs. The most suitable mechanism identified was validated by building and testing a prototype.

Keywords: add-on device, Rocker-Bogie, stair climbing, star wheel, y wheel

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2955 The Design and Implementation of a Calorimeter for Evaluation of the Thermal Performance of Materials: The Case of Phase Change Materials

Authors: Ebrahim Solgi, Zahra Hamedani, Behrouz Mohammad Kari, Ruwan Fernando, Henry Skates

Abstract:

The use of thermal energy storage (TES) as part of a passive design strategy can reduce a building’s energy demand. TES materials do this by increasing the lag between energy consumption and energy supply by absorbing, storing and releasing energy in a controlled manner. The increase of lightweight construction in the building industry has made it harder to utilize thermal mass. Consequently, Phase Change Materials (PCMs) are a promising alternative as they can be manufactured in thin layers and used with lightweight construction to store latent heat. This research investigates utilizing PCMs, with the first step being measuring their performance under experimental conditions. To do this requires three components. The first is a calorimeter for measuring indoor thermal conditions, the second is a pyranometer for recording the solar conditions: global, diffuse and direct radiation and the third is a data-logger for recording temperature and humidity for the studied period. This paper reports on the design and implementation of an experimental setup used to measure the thermal characteristics of PCMs as part of a wall construction. The experimental model has been simulated with the software EnergyPlus to create a reliable simulation model that warrants further investigation.

Keywords: phase change materials, EnergyPlus, experimental evaluation, night ventilation

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2954 Long Term Monitoring and Assessment of Atmospheric Aerosols in Indo-Gangetic Region of India

Authors: Ningombam Linthoingambi Devi, Amrendra Kumar

Abstract:

The long term sampling at one of the most populated city in Indo-Gangetic region shows higher mass concentration of atmospheric aerosol (PM₂.₅) during spring season (144.70µg/m³), summer season (91.96 µg/m³), the autumn season (266.48µg/m³) and winter season (367.09 µg/m³) respectively. The concentration of PM₂.₅ in Patna across the year shows much higher than the limit fixed by the national ambient air quality level fixed by central pollution control board India (CPCB, India) and World Health Organization (WHO). Different water-soluble cation (Na⁺, K⁺, Ca²⁺, NH₄⁺ , and Mg²⁺) and anion (Cl⁻, NO₃⁻ , and SO₄²⁻) species were detected in PM₂.₅. Results show the significantly higher loaded of water-soluble ions during winter and spring seasons. The acidity of the atmosphere was revealed and calculated using selected major cations (K⁺, Ca²⁺ , and NH₄⁺) and anions (SO₄²⁻, and NO₃⁻). A regression correlation was analyzed to check the significant linkage between the acidity and alkalinity ions. During the winter season (r² = 0.79) and spring season (r² = 0.64) shows good significant correlation between the cations and anions. The ratio of NO₃⁻/SO₄²⁻ indicates the sources of secondary pollutants were mainly influenced by industrial and vehicular emission however SO₄²⁻ mostly emitted from industries during the winter season.

Keywords: aerosols, inorganic species, source apportionment, Indo-Gangetic region

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2953 FEM Simulation of Triple Diffusive Magnetohydrodynamics Effect of Nanofluid Flow over a Nonlinear Stretching Sheet

Authors: Rangoli Goyal, Rama Bhargava

Abstract:

The triple diffusive boundary layer flow of nanofluid under the action of constant magnetic field over a non-linear stretching sheet has been investigated numerically. The model includes the effect of Brownian motion, thermophoresis, and cross-diffusion; slip mechanisms which are primarily responsible for the enhancement of the convective features of nanofluid. The governing partial differential equations are transformed into a system of ordinary differential equations (by using group theory transformations) and solved numerically by using variational finite element method. The effects of various controlling parameters, such as the magnetic influence number, thermophoresis parameter, Brownian motion parameter, modified Dufour parameter, and Dufour solutal Lewis number, on the fluid flow as well as on heat and mass transfer coefficients (both of solute and nanofluid) are presented graphically and discussed quantitatively. The present study has industrial applications in aerodynamic extrusion of plastic sheets, coating and suspensions, melt spinning, hot rolling, wire drawing, glass-fibre production, and manufacture of polymer and rubber sheets, where the quality of the desired product depends on the stretching rate as well as external field including magnetic effects.

Keywords: FEM, thermophoresis, diffusiophoresis, Brownian motion

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2952 Facial Infiltrating Lipomatosis, a Rare Cause of Facial Asymmetry to Be Known: Case Report and Literature Review

Authors: Shantanu Vyas, Neerja Meena

Abstract:

Facial infiltrating lipomatosis is a rare lipomatous lesion, first described by Slavin in 1983. It is a benign pseudotumor pathology. It corresponds to a non-encapsulated collection of mature adipocytes infiltrating the local tissue and hyperplasia of underlying bone leading to a craniofacial deformity. Very few cases have been reported in the literature. We report the case of a 19-year-old female patient, who was consulted for a swelling of the right hemiface progressively evolving since birth. Physical examination revealed facial asymmetry. On palpation, the mass was soft, painless, not compressible, not pulsatile, not fluctuating. In view of the asymptomatic nature and slow progression of the lesion, a lipomatous tumour, namely lipoma, was suggested. CT scan image shows a hyperplastic subcutaneous fat on the right hemiface. On the right jugal and temporal areas, there is a subcutaneous formation of fatty density, poorly limited, with no detectable peripheral capsule. It merges with the adjacent fat. In the bone window, there was a hyperplasia of underlying bone. Facial lipomatosis infiltration of the face is a benign pseudotumor pathology. As a result, it can be confused with other disorders, in particular, hemifacial hyperplasia. Combination of physical and radiological findings can establish the diagnosis. Surgical treatment is done for cosmetic purposes.

Keywords: cosmetic correction and facial assemetry, aesthetic results, facial infiltration, surgery

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2951 Real-World PM, PN and NOx Emission Differences among DOC+CDPF Retrofit Diesel-, Diesel- And Natural Gas-Fueled Bus

Authors: Zhiwen Yang, Jingyuan Li, Zhenkai Xie, Jian Ling, Jiguang Wang, Mengliang Li

Abstract:

To reflect the effects of different emission control strategies, such as retrofitting after-treatment system and replacing with natural gas-fueled vehicles, on particle number (PN), particle mass (PM) and nitrogen oxides (NOx) emissions emitted by urban bus, a portable emission measurement system (PEMS) was employed herein to conduct real-world driving emission measurements on a diesel oxidation catalytic converter (DOC) and catalyzed diesel particulate filter (CDPF) retrofitting China IV diesel bus, a China IV diesel bus, and a China V natural gas bus. The results show that both tested diesel buses possess markedly advantages in NOx emission control when compared to the lean-burn natural gas bus equipped without any NOx after-treatment system. As to PN and PM, only the DOC+CDPF retrofitting diesel bus exhibits enormous benefits on emission control relate to the natural gas bus, especially the normal diesel bus. Meanwhile, the differences in PM and PN emissions between retrofitted and normal diesel buses generally increase with the increase in vehicle-specific power (VSP). Furthermore, the differences in PM emissions, especially those in the higher VSP ranges, are more significant than those in PN. In addition, the maximum peak PN particle size (32 nm) of the retrofitted diesel bus was significantly lower than that of the normal diesel bus (100 nm). These phenomena indicate that the CDPF retrofitting can effectively reduce diesel bus exhaust particle emissions, especially those with large particle sizes.

Keywords: CDPF, diesel, natural gas, real-world emissions

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2950 The Iconic Pink Donut Box: An Analysis of Memory and Identity Amongst Cambodian Refugees in California

Authors: Basmah Arshad

Abstract:

In the aftermath of the Cambodian genocide, many refugees resettled in America. They carved out a distinctively Cambodian-American space in California with donut shops, establishing a tight-knit community that worked to achieve ‘the American dream’. Urged by traumatic memories of the genocide and American society directly encouraging (if not demanding) cultural assimilation, these refugees and successive generations continuously worked to re-identify themselves as Americans. Artist Phung Huynh grew up in this context of family-owned donut shops and the frantic scramble for stability and security. It is this community that she depicts in her artwork series from the late 2010s, ‘Khmerican: Drawing on Pink Donut Boxes’. Huynh's artwork challenges dominant Western narratives about the Cambodian genocide by pushing forward images of resilience, resistance, and joy, while also allowing for a discussion about issues of assimilation, identity, and nostalgia in the Cambodian-American community. It also provokes deeply relevant questions about how refugees and immigrants deliberately appropriate elements of the Americana (eg, donuts) to assimilate and re-fashion their identity as a tactic for financial stability and social survival.

Keywords: Cambodian diaspora, cultural identity, assimilation, food, artwork

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