Search results for: naturalistic environments
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1957

Search results for: naturalistic environments

397 Removal of Methylene Blue from Aqueous Solution by Adsorption onto Untreated Coffee Grounds

Authors: N. Azouaou, H. Mokaddem, D. Senadjki, K. Kedjit, Z. Sadaoui

Abstract:

Introduction: Water contamination caused by dye industries, including food, leather, textile, plastic, cosmetics, paper-making, printing and dye synthesis, has caused more and more attention, since most dyes are harmful to human being and environments. Untreated coffee grounds were used as a high-efficiency adsorbent for the removal of a cationic dye (methylene blue, MB) from aqueous solution. Characterization of the adsorbent was performed using several techniques such as SEM, surface area (BET), FTIR and pH zero charge. The effects of contact time, adsorbent dose, initial solution pH and initial concentration were systematically investigated. Results showed the adsorption kinetics followed the pseudo-second-order kinetic model. Langmuir isotherm model is in good agreement with the experimental data as compared to Freundlich and D–R models. The maximum adsorption capacity was found equal to 52.63mg/g. In addition, the possible adsorption mechanism was also proposed based on the experimental results. Experimental: The adsorption experiments were carried out in batch at room temperature. A given mass of adsorbent was added to methylene blue (MB) solution and the entirety was agitated during a certain time. The samples were carried out at quite time intervals. The concentrations of MB left in supernatant solutions after different time intervals were determined using a UV–vis spectrophotometer. The amount of MB adsorbed per unit mass of coffee grounds (qt) and the dye removal efficiency (R %) were evaluated. Results and Discussion: Some chemical and physical characteristics of coffee grounds are presented and the morphological analysis of the adsorbent was also studied. Conclusions: The good capacity of untreated coffee grounds to remove MB from aqueous solution was demonstrated in this study, highlighting its potential for effluent treatment processes. The kinetic experiments show that the adsorption is rapid and maximum adsorption capacities qmax= 52.63mg/g achieved in 30min. The adsorption process is a function of the adsorbent concentration, pH and metal ion concentration. The optimal parameters found are adsorbent dose m=5g, pH=5 and ambient temperature. FTIR spectra showed that the principal functional sites taking part in the sorption process included carboxyl and hydroxyl groups.

Keywords: adsorption, methylene blue, coffee grounds, kinetic study

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396 Evaluation of Teaching Team Stress Factors in Two Engineering Education Programs

Authors: Kari Bjorn

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Team learning has been studied and modeled as double loop model and its variations. Also, metacognition has been suggested as a concept to describe the nature of team learning to be more than a simple sum of individual learning of the team members. Team learning has a positive correlation with both individual motivation of its members, as well as the collective factors within the team. Team learning of previously very independent members of two teaching teams is analyzed. Applied Science Universities are training future professionals with ever more diversified and multidisciplinary skills. The size of the units of teaching and learning are increasingly larger for several reasons. First, multi-disciplinary skill development requires more active learning and richer learning environments and learning experiences. This occurs on students teams. Secondly, teaching of multidisciplinary skills requires a multidisciplinary and team-based teaching from the teachers as well. Team formation phases have been identifies and widely accepted. Team role stress has been analyzed in project teams. Projects typically have a well-defined goal and organization. This paper explores team stress of two teacher teams in a parallel running two course units in engineering education. The first is an Industrial Automation Technology and the second is Development of Medical Devices. The courses have a separate student group, and they are in different campuses. Both are run in parallel within 8 week time. Both of them are taught by a group of four teachers with several years of teaching experience, but individually. The team role stress scale items - the survey is done to both teaching groups at the beginning of the course and at the end of the course. The inventory of questions covers the factors of ambiguity, conflict, quantitative role overload and qualitative role overload. Some comparison to the study on project teams can be drawn. Team development stage of the two teaching groups is different. Relating the team role stress factors to the development stage of the group can reveal the potential of management actions to promote team building and to understand the maturity of functional and well-established teams. Mature teams indicate higher job satisfaction and deliver higher performance. Especially, teaching teams who deliver highly intangible results of learning outcome are sensitive to issues in the job satisfaction and team conflicts. Because team teaching is increasing, the paper provides a review of the relevant theories and initial comparative and longitudinal results of the team role stress factors applied to teaching teams.

Keywords: engineering education, stress, team role, team teaching

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395 The Response of Mammal Populations to Abrupt Changes in Fire Regimes in Montane Landscapes of South-Eastern Australia

Authors: Jeremy Johnson, Craig Nitschke, Luke Kelly

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Fire regimes, climate and topographic gradients interact to influence ecosystem structure and function across fire-prone, montane landscapes worldwide. Biota have developed a range of adaptations to historic fire regime thresholds, which allow them to persist in these environments. In south-eastern Australia, a signal of fire regime changes is emerging across these landscapes, and anthropogenic climate change is likely to be one of the main drivers of an increase in burnt area and more frequent wildfire over the last 25 years. This shift has the potential to modify vegetation structure and composition at broad scales, which may lead to landscape patterns to which biota are not adapted, increasing the likelihood of local extirpation of some mammal species. This study aimed to address concerns related to the influence of abrupt changes in fire regimes on mammal populations in montane landscapes. It first examined the impact of climate, topography, and vegetation on fire patterns and then explored the consequences of these changes on mammal populations and their habitats. Field studies were undertaken across diverse vegetation, fire severity and fire frequency gradients, utilising camera trapping and passive acoustic monitoring methodologies and the collection of fine-scale vegetation data. Results show that drought is a primary contributor to fire regime shifts at the landscape scale, while topographic factors have a variable influence on wildfire occurrence at finer scales. Frequent, high severity wildfire influenced forest structure and composition at broad spatial scales, and at fine scales, it reduced occurrence of hollow-bearing trees and promoted coarse woody debris. Mammals responded differently to shifts in forest structure and composition depending on their habitat requirements. This study highlights the complex interplay between fire regimes, environmental gradients, and biotic adaptations across temporal and spatial scales. It emphasizes the importance of understanding complex interactions to effectively manage fire-prone ecosystems in the face of climate change.

Keywords: fire, ecology, biodiversity, landscape ecology

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394 Synthesis and Characterization of pH-Responsive Nanocarriers Based on POEOMA-b-PDPA Block Copolymers for RNA Delivery

Authors: Bruno Baptista, Andreia S. R. Oliveira, Patricia V. Mendonca, Jorge F. J. Coelho, Fani Sousa

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Drug delivery systems are designed to allow adequate protection and controlled delivery of drugs to specific locations. These systems aim to reduce side effects and control the biodistribution profile of drugs, thus improving therapeutic efficacy. This study involved the synthesis of polymeric nanoparticles, based on amphiphilic diblock copolymers, comprising a biocompatible, poly (oligo (ethylene oxide) methyl ether methacrylate (POEOMA) as hydrophilic segment and a pH-sensitive block, the poly (2-diisopropylamino)ethyl methacrylate) (PDPA). The objective of this work was the development of polymeric pH-responsive nanoparticles to encapsulate and carry small RNAs as a model to further develop non-coding RNAs delivery systems with therapeutic value. The responsiveness of PDPA to pH allows the electrostatic interaction of these copolymers with nucleic acids at acidic pH, as a result of the protonation of the tertiary amine groups of this polymer at pH values below its pKa (around 6.2). Initially, the molecular weight parameters and chemical structure of the block copolymers were determined by size exclusion chromatography (SEC) and nuclear magnetic resonance (1H-NMR) spectroscopy, respectively. Then, the complexation with small RNAs was verified, generating polyplexes with sizes ranging from 300 to 600 nm and with encapsulation efficiencies around 80%, depending on the molecular weight of the polymers, their composition, and concentration used. The effect of pH on the morphology of nanoparticles was evaluated by scanning electron microscopy (SEM) being verified that at higher pH values, particles tend to lose their spherical shape. Since this work aims to develop systems for the delivery of non-coding RNAs, studies on RNA protection (contact with RNase, FBS, and Trypsin) and cell viability were also carried out. It was found that they induce some protection against constituents of the cellular environment and have no cellular toxicity. In summary, this research work contributes to the development of pH-sensitive polymers, capable of protecting and encapsulating RNA, in a relatively simple and efficient manner, to further be applied on drug delivery to specific sites where pH may have a critical role, as it can occur in several cancer environments.

Keywords: drug delivery systems, pH-responsive polymers, POEOMA-b-PDPA, small RNAs

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393 The Effect of Filter Design and Face Velocity on Air Filter Performance

Authors: Iyad Al-Attar

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Air filters installed in HVAC equipment and gas turbine for power generation confront several atmospheric contaminants with various concentrations while operating in different environments (tropical, coastal, hot). This leads to engine performance degradation, as contaminants are capable of deteriorating components and fouling compressor assembly. Compressor fouling is responsible for 70 to 85% of gas turbine performance degradation leading to reduction in power output and availability and an increase in the heat rate and fuel consumption. Therefore, filter design must take into account face velocities, pleat count and its corresponding surface area; to verify filter performance characteristics (Efficiency and Pressure Drop). The experimental work undertaken in the current study examined two groups of four filters with different pleating densities were investigated for the initial pressure drop response and fractional efficiencies. The pleating densities used for this study is 28, 30, 32 and 34 pleats per 100mm for each pleated panel and measured for ten different flow rates ranging from 500 to 5000 m3/h with increment of 500m3/h. This experimental work of the current work has highlighted the underlying reasons behind the reduction in filter permeability due to the increase in face velocity and pleat density. The reasons that led to surface area losses of filtration media are due to one or combination of the following effects: pleat-crowding, deflection of the entire pleated panel, pleat distortion at the corner of the pleat and/or filtration medium compression. It is evident from entire array of experiments that as the particle size increases, the efficiency decreases until the MPPS is reached. Beyond the MPPS, the efficiency increases with increase in particle size. The MPPS shifts to a smaller particle size as the face velocity increases, while the pleating density and orientation did not have a pronounced effect on the MPPS. Throughout the study, an optimal pleat count which satisfies initial pressure drop and efficiency requirements may not have necessarily existed. The work has also suggested that a valid comparison of the pleat densities should be based on the effective surface area that participates in the filtration action and not the total surface area the pleat density provides.

Keywords: air filters, fractional efficiency, gas cleaning, glass fibre, HEPA filter, permeability, pressure drop

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392 Overview of Environmental and Economic Theories of the Impact of Dams in Different Regions

Authors: Ariadne Katsouras, Andrea Chareunsy

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The number of large hydroelectric dams in the world has increased from almost 6,000 in the 1950s to over 45,000 in 2000. Dams are often built to increase the economic development of a country. This can occur in several ways. Large dams take many years to build so the construction process employs many people for a long time and that increased production and income can flow on into other sectors of the economy. Additionally, the provision of electricity can help raise people’s living standards and if the electricity is sold to another country then the money can be used to provide other public goods for the residents of the country that own the dam. Dams are also built to control flooding and provide irrigation water. Most dams are of these types. This paper will give an overview of the environmental and economic theories of the impact of dams in different regions of the world. There is a difference in the degree of environmental and economic impacts due to the varying climates and varying social and political factors of the regions. Production of greenhouse gases from the dam’s reservoir, for instance, tends to be higher in tropical areas as opposed to Nordic environments. However, there are also common impacts due to construction of the dam itself, such as, flooding of land for the creation of the reservoir and displacement of local populations. Economically, the local population tends to benefit least from the construction of the dam. Additionally, if a foreign company owns the dam or the government subsidises the cost of electricity to businesses, then the funds from electricity production do not benefit the residents of the country the dam is built in. So, in the end, the dams can benefit a country economically, but the varying factors related to its construction and how these are dealt with, determine the level of benefit, if any, of the dam. Some of the theories or practices used to evaluate the potential value of a dam include cost-benefit analysis, environmental impacts assessments and regressions. Systems analysis is also a useful method. While these theories have value, there are also possible shortcomings. Cost-benefit analysis converts all the costs and benefits to dollar values, which can be problematic. Environmental impact assessments, likewise, can be incomplete, especially if the assessment does not include feedback effects, that is, they only consider the initial impact. Finally, regression analysis is dependent on the available data and again would not necessarily include feedbacks. Systems analysis is a method that can allow more complex modelling of the environment and the economic system. It would allow a clearer picture to emerge of the impacts and can include a long time frame.

Keywords: comparison, economics, environment, hydroelectric dams

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391 Cyber Bullying, Online Risks and Parental Mediation: A Comparison between Adolescent Reports and Parent Perceptions in South Africa

Authors: Masa Popovac, Philip Fine

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Information and Communication Technologies (ICTs) have altered our social environments, and young people in particular have immersed themselves in the digital age. Despite countless benefits, younger ICT users are being exposed to various online risks such as contact with strangers, viewing of risky content, sending or receiving sexually themed images or comments (i.e. ‘sexting’) as well as cyber bullying. Parents may not be fully aware of the online spaces their children inhabit and often struggle to implement effective mediation strategies. This quantitative study explored (i) three types of online risks (contact risks, content risks and conduct risks), (ii) cyber bullying victimization and perpetration, and (iii) parental mediation among a sample of 689 South African adolescents aged between 12-17 years. Survey data was also collected for 227 of their parents relating to their perceptions of their child’s online experiences. A comparison between adolescent behaviors and parental perceptions was examined on the three variables in the study. Findings reveal various online risk taking behaviors. In terms of contact risks, 56% of adolescents reported having contact with at least one online stranger, with many meeting these strangers in person. Content risks included exposure to harmful information such as websites promoting extreme diets or self-harm as well as inappropriate content: 84% of adolescents had seen violent content and 75% had seen sexual content online. Almost 60% of adolescents engaged in conduct risks such as sexting. Eight online victimization behaviors were examined in the study and 79% of adolescents had at least one of these negative experiences, with a third (34%) defining this experience as cyber bullying. A strong connection between victimization and perpetration was found, with 63% of adolescents being both a victim and perpetrator. Very little parental mediation of ICT use was reported. Inferential statistics revealed that parents consistently underestimated their child’s online risk taking behaviors as well as their cyber bullying victimization and perpetration. Parents also overestimated mediation strategies in the home. The generational gap in the knowledge and use of ICTs is a barrier to effective parental mediation and online safety, since many negative online experiences by adolescents go undetected and can continue for extended periods of time thereby exacerbating the potential psychological and emotional distress. The study highlights the importance of including parents in online safety efforts.

Keywords: cyber bullying, online risk behaviors, parental mediation, South Africa

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390 Architectural Identity in Manifestation of Tall-buildings' Design

Authors: Huda Arshadlamphon

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Advancing frontiers of technology and industry is moving rapidly fast influenced by the economic and political phenomena. One vital phenomenon,which has had consolidated the world to a one single village, is Globalization. In response, architecture and the built-environment have faced numerous changes, adjustments, and developments. Tall-buildings, as a product of globalization, represent prestigious icons, symbols, and landmarks for highly economics and advanced countries. Despite the fact, this trend has been encountering several design challenges incorporating architectural identity, traditions, and characteristics that enhance the built-environments' sociocultural values and traditions. The necessity of these values and traditionsform self-solitarily, leading to visual and spatial creativity, independency, and individuality. In other words, they maintain the inherited identity and avoid replications in all means and aspects. This paper, firstly, defines globalization phenomenon, architectural identity, and the concerns of sociocultural values in relation to the traditional characteristics of the built-environment. Secondly, through three case-studies of tall-buildings located in Jeddah city, Saudi Arabia, the Queen's Building, the National Commercial Bank Building (NCB), and the Islamic Development Bank Building; design strategies and methodologies in acclimating architectural identity and characteristics in tall-buildings are discussed. The case-studies highlight buildings' sites and surroundings, concepts and inspirations, design elements, architectural forms and compositions, characteristics, issues, barriers, and trammels facing the designs' decisions, representation of facades, and selection of materials and colors. Furthermore, the research will elucidate briefs of the dominant factors that shape the architectural identity of Jeddah city. In conclusion, the study manifests four tall-buildings' design standards guideline in preserving and developing architectural identity in Jeddah city; the scale of urban and natural environment, the scale of architectural design elements, the integration of visual images, and the creation of spatial scenes and scenarios. The prosed guideline will encourage the development of architectural identity aligned with zeitgeist demands and requirements, supports the contemporary architectural movement toward tall-buildings, and shoresself-solitarily in representing sociocultural values and traditions of the built-environment.

Keywords: architectural identity, built-environment, globalization, sociocultural values and traditions, tall-buildings

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389 Cooperative Learning Promotes Successful Learning. A Qualitative Study to Analyze Factors that Promote Interaction and Cooperation among Students in Blended Learning Environments

Authors: Pia Kastl

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Potentials of blended learning are the flexibility of learning and the possibility to get in touch with lecturers and fellow students on site. By combining face-to-face sessions with digital self-learning units, the learning process can be optimized, and learning success increased. To examine wether blended learning outperforms online and face-to-face teaching, a theory-based questionnaire survey was conducted. The results show that the interaction and cooperation among students is poorly provided in blended learning, and face-to-face teaching performs better in this respect. The aim of this article is to identify concrete suggestions students have for improving cooperation and interaction in blended learning courses. For this purpose, interviews were conducted with students from various academic disciplines in face-to-face, online, or blended learning courses (N= 60). The questions referred to opinions and suggestions for improvement regarding the course design of the respective learning environment. The analysis was carried out by qualitative content analysis. The results show that students perceive the interaction as beneficial to their learning. They verbalize their knowledge and are exposed to different perspectives. In addition, emotional support is particularly important in exam phases. Interaction and cooperation were primarily enabled in the face-to-face component of the courses studied, while there was very limited contact with fellow students in the asynchronous component. Forums offered were hardly used or not used at all because the barrier to asking a question publicly is too high, and students prefer private channels for communication. This is accompanied by the disadvantage that the interaction occurs only among people who already know each other. Creating contacts is not fostered in the blended learning courses. Students consider optimization possibilities as a task of the lecturers in the face-to-face sessions: Here, interaction and cooperation should be encouraged through get-to-know-you rounds or group work. It is important here to group the participants randomly to establish contact with new people. In addition, sufficient time for interaction is desired in the lecture, e.g., in the context of discussions or partner work. In the digital component, students prefer synchronous exchange at a fixed time, for example, in breakout rooms or an MS Teams channel. The results provide an overview of how interaction and cooperation can be implemented in blended learning courses. Positive design possibilities are partly dependent on subject area and course. Future studies could tie in here with a course-specific analysis.

Keywords: blended learning, higher education, hybrid teaching, qualitative research, student learning

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388 Urban Compactness and Sustainability: Beijing Experience

Authors: Xilu Liu, Ameen Farooq

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Beijing has several compact residential housing settings in many of its urban districts. The study in this paper reveals that urban compactness, as predictor of density, may carry an altogether different meaning in the developing world when compared to the U.S for achieving objectives of urban sustainability. Recent urban design studies in the U.S are debating for compact and mixed-use higher density housing to achieve sustainable and energy efficient living environments. While the concept of urban compactness is widely accepted as an approach in modern architectural and urban design fields, this belief may not directly carry well into all areas within cities of developing countries. Beijing’s technology-driven economy, with its historic and rich cultural heritage and a highly speculated real-estate market, extends its urban boundaries into multiple compact urban settings of varying scales and densities. The accelerated pace of migration from the countryside for better opportunities has led to unsustainable and uncontrolled buildups in order to meet the growing population demand within and outside of the urban center. This unwarranted compactness in certain urban zones has produced an unhealthy physical density with serious environmental and ecological challenging basic living conditions. In addition, crowding, traffic congestion, pollution and limited housing surrounding this compactness is a threat to public health. Several residential blocks in close proximity to each other were found quite compacted, or ill-planned, with residential sites due to lack of proper planning in Beijing. Most of them at first sight appear to be compact and dense but further analytical studies revealed that what appear to be dense actually are not as dense as to make a good case that could serve as the corner stone of sustainability and energy efficiency. This study considered several factors including floor area ratio (FAR), ground coverage (GSI), open space ratio (OSR) as indicators in analyzing urban compactness as a predictor of density. The findings suggest that these measures, influencing the density of residential sites under study, were much smaller in density than expected given their compact adjacencies. Further analysis revealed that several residential housing appear to support the notion of density in its compact layout but are actually compacted due to unregulated planning marred by lack of proper urban design standards, policies and guidelines specific to their urban context and condition.

Keywords: Beijing, density, sustainability, urban compactness

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387 725 Arcadia Street in Pretoria: A Pretoria Case Study Focusing on Urban Acupuncture

Authors: Konrad Steyn, Jacques Laubscher

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South African urban design solutions are mostly aligned with European and North American models that are often not appropriate in addressing some of this country’s challenges such as multiculturalism and decaying urban areas. Sustainable urban redevelopment in South Africa should be comprehensive in nature, sensitive in its manifestation, and should be robust and inclusive in order to achieve social relevance. This paper argues that the success of an urban design intervention is largely dependent on the public’s perceptions and expectations, and the way people participate in shaping their environments. The concept of sustainable urbanism is thus more comprehensive than – yet should undoubtedly include – methods of construction, material usage and climate control principles. The case study is a central element of this research paper. 725 Arcadia Street in Pretoria, was originally commissioned as a food market structure. A starkly contrasting existing modernist adjacent building forms the morphological background. Built in 1969, it is a valuable part of Pretoria’s modernist fabric. It was realised early on that the project should not be a mere localised architectural intervention, but rather an occasion to revitalise the neighbourhood through urban regeneration. Because of the complex and comprehensive nature of the site and rich cultural diversity of the area, a multi-faceted approach seemed the most appropriate response. The methodology for collating data consisted of a combination of literature reviews (regarding the historic original fauna and flora and current plants, observation (frequent site visits) and physical surveying on the neighbourhood level (physical location, connectivity to surrounding landmarks as well as movement systems and pedestrian flows). This was followed by an exploratory design phase, culminating in the present redevelopment proposal. Since built environment interventions are increasingly based on generalised normative guidelines, an approach focusing of urban acupuncture could serve as an alternative. Celebrating the specific urban condition, urban acupuncture offers an opportunity to influence the surrounding urban fabric and achieve urban renewal through physical, social and cultural mediation.

Keywords: neighbourhood, urban renewal, South African urban design solutions, sustainable urban redevelopment

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386 Decision-Making in Higher Education: Case Studies Demonstrating the Value of Institutional Effectiveness Tools

Authors: Carolinda Douglass

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Institutional Effectiveness (IE) is the purposeful integration of functions that foster student success and support institutional performance. IE is growing rapidly within higher education as it is increasingly viewed by higher education administrators as a beneficial approach for promoting data-informed decision-making in campus-wide strategic planning and execution of strategic initiatives. Specific IE tools, including, but not limited to, project management; impactful collaboration and communication; commitment to continuous quality improvement; and accountability through rigorous evaluation; are gaining momentum under the auspices of IE. This research utilizes a case study approach to examine the use of these IE tools, highlight successes of this use, and identify areas for improvement in the implementation of IE tools within higher education. The research includes three case studies: (1) improving upon academic program review processes including the assessment of student learning outcomes as a core component of program quality; (2) revising an institutional vision, mission, and core values; and (3) successfully navigating an institution-wide re-accreditation process. Several methods of data collection are embedded within the case studies, including surveys, focus groups, interviews, and document analyses. Subjects of these methods include higher education administrators, faculty, and staff. Key findings from the research include areas of success and areas for improvement in the use of IE tools associated with specific case studies as well as aggregated results across case studies. For example, the use of case management proved useful in all of the case studies, while rigorous evaluation did not uniformly provide the value-added that was expected by higher education decision-makers. The use of multiple IE tools was shown to be consistently useful in decision-making when applied with appropriate awareness of and sensitivity to core institutional culture (for example, institutional mission, local environments and communities, disciplinary distinctions, and labor relations). As IE gains a stronger foothold in higher education, leaders in higher education can make judicious use of IE tools to promote better decision-making and secure improved outcomes of strategic planning and the execution of strategic initiatives.

Keywords: accreditation, data-informed decision-making, higher education management, institutional effectiveness tools, institutional mission, program review, strategic planning

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385 Qualitative Analysis of User Experiences and Needs for Educational Chatbots in Higher Education

Authors: Felix Golla

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In an era where technology increasingly intersects with education, the potential of chatbots and ChatGPT agents in enhancing student learning experiences in higher education is both significant and timely. This study explores the integration of these AI-driven tools in educational settings, emphasizing their design and functionality to meet the specific needs of students. Recognizing the gap in literature concerning student-centered AI applications in education, this research offers valuable insights into the role and efficacy of chatbots and ChatGPT agents as educational tools. Employing qualitative research methodologies, the study involved conducting semi-structured interviews with university students. These interviews were designed to gather in-depth insights into the students' experiences and expectations regarding the use of AI in learning environments. The High-Performance Cycle Model, renowned for its focus on goal setting and motivation, served as the theoretical framework guiding the analysis. This model helped in systematically categorizing and interpreting the data, revealing the nuanced perceptions and preferences of students regarding AI tools in education. The major findings of the study indicate a strong preference among students for chatbots and ChatGPT agents that offer personalized interaction, adaptive learning support, and regular, constructive feedback. These features were deemed essential for enhancing student engagement, motivation, and overall learning outcomes. Furthermore, the study revealed that students perceive these AI tools not just as passive sources of information but as active facilitators in the learning process, capable of adapting to individual learning styles and needs. In conclusion, this study underscores the transformative potential of chatbots and ChatGPT agents in higher education. It highlights the need for these AI tools to be designed with a student-centered approach, ensuring their alignment with educational objectives and student preferences. The findings contribute to the evolving discourse on AI in education, suggesting a paradigm shift towards more interactive, responsive, and personalized learning experiences. This research not only informs educators and technologists about the desirable features of educational chatbots but also opens avenues for future studies to explore the long-term impact of AI integration in academic curricula.

Keywords: chatbot design in education, high-performance cycle model application, qualitative research in AI, student-centered learning technologies

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384 Quantum Graph Approach for Energy and Information Transfer through Networks of Cables

Authors: Mubarack Ahmed, Gabriele Gradoni, Stephen C. Creagh, Gregor Tanner

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High-frequency cables commonly connect modern devices and sensors. Interestingly, the proportion of electric components is rising fast in an attempt to achieve lighter and greener devices. Modelling the propagation of signals through these cable networks in the presence of parameter uncertainty is a daunting task. In this work, we study the response of high-frequency cable networks using both Transmission Line and Quantum Graph (QG) theories. We have successfully compared the two theories in terms of reflection spectra using measurements on real, lossy cables. We have derived a generalisation of the vertex scattering matrix to include non-uniform networks – networks of cables with different characteristic impedances and propagation constants. The QG model implicitly takes into account the pseudo-chaotic behavior, at the vertices, of the propagating electric signal. We have successfully compared the asymptotic growth of eigenvalues of the Laplacian with the predictions of Weyl law. We investigate the nearest-neighbour level-spacing distribution of the resonances and compare our results with the predictions of Random Matrix Theory (RMT). To achieve this, we will compare our graphs with the generalisation of Wigner distribution for open systems. The problem of scattering from networks of cables can also provide an analogue model for wireless communication in highly reverberant environments. In this context, we provide a preliminary analysis of the statistics of communication capacity for communication across cable networks, whose eventual aim is to enable detailed laboratory testing of information transfer rates using software defined radio. We specialise this analysis in particular for the case of MIMO (Multiple-Input Multiple-Output) protocols. We have successfully validated our QG model with both TL model and laboratory measurements. The growth of Eigenvalues compares well with Weyl’s law and the level-spacing distribution agrees so well RMT predictions. The results we achieved in the MIMO application compares favourably with the prediction of a parallel on-going research (sponsored by NEMF21.)

Keywords: eigenvalues, multiple-input multiple-output, quantum graph, random matrix theory, transmission line

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383 Advancing Microstructure Evolution in Tungsten Through Rolling in Laser Powder Bed Fusion

Authors: Narges Shayesteh Moghaddam

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Tungsten (W), a refractory metal known for its remarkably high melting temperature, offers tremendous potential for use in challenging environments prevalent in sectors such as space exploration, defense, and nuclear industries. Additive manufacturing, especially the Laser Powder-Bed Fusion (LPBF) technique, emerges as a beneficial method for fabricating tungsten parts. This technique enables the production of intricate components while simultaneously reducing production lead times and associated costs. However, the inherent brittleness of tungsten and its tendency to crack under high-temperature conditions pose significant challenges to the manufacturing process. Our research primarily focuses on the process of rolling tungsten parts in a layer-by-layer manner in LPBF and the subsequent changes in microstructure. Our objective is not only to identify the alterations in the microstructure but also to assess their implications on the physical properties and performance of the fabricated tungsten parts. To examine these aspects, we conducted an extensive series of experiments that included the fabrication of tungsten samples through LPBF and subsequent characterization using advanced materials analysis techniques. These investigations allowed us to scrutinize shifts in various microstructural features, including, but not limited to, grain size and grain boundaries occurring during the rolling process. The results of our study provide crucial insights into how specific factors, such as plastic deformation occurring during the rolling process, influence the microstructural characteristics of the fabricated parts. This information is vital as it provides a foundation for understanding how the parameters of the layer-by-layer rolling process affect the final tungsten parts. Our research significantly broadens the current understanding of microstructural evolution in tungsten parts produced via the layer-by-layer rolling process in LPBF. The insights obtained will play a pivotal role in refining and optimizing manufacturing parameters, thus improving the mechanical properties of tungsten parts and, therefore, enhancing their performance. Furthermore, these findings will contribute to the advancement of manufacturing techniques, facilitating the wider application of tungsten parts in various high-demand sectors. Through these advancements, this research represents a significant step towards harnessing the full potential of tungsten in high-temperature and high-stress applications.

Keywords: additive manufacturing, rolling, tungsten, refractory materials

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382 Middle Ordovician (Llanvirnian) Relative Sea-Level Fluctuations

Authors: Ying Jia Teoh

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The Canning Basin is located between the Kimberley and Pilbara Precambrian cratonic blocks. It is a large but relatively poorly explored Paleozoic basin in remote Western Australia. During the early Ordovician period, the Australian continent was located near the equator. Middle Ordovician age Nita and Goldwyer Formations in Canning Basin are therefore warm water carbonates. The Nita Formation carbonates are a regressive sequence which conformably overlies the Goldwyer Formation. It contains numerous progradational cycles of limestone, vuggy dolomitized carbonate beds and shale deposited in subtidal to supratidal environments. The Goldwyer Formation contains transgressive shale sequences and regressive carbonates deposited in shallow subtidal conditions. The shales contain oil-prone Gloeocapsormorpha prisca-bearing source rocks. Llanvirnian relative sea-level fluctuations were reconstructed by using Fischer plots methodology for three key wells (wells McLarty 1, Looma 1 and Robert 1) in Broome Platform and compared with INPEFA data. The Goldwyer lower shale (interval Or1000P) shows increasing relative sea-level and this matches with a transgressive systems tract. Goldwyer middle carbonate (interval Or2000) shows relative sea-level drop and this matches with a regressive systems tract. Goldwyer upper shale (interval Or2000P) shows relative sea-level drop and this matches with a transgressive systems tract. Nita Formation Leo Member (interval Or3000) shows a relative sea level drop and this matches with a regressive systems tract. The Nita Formation Cudalgarra Member (intervals Or3000P and Or4000) with transgressive systems tract then this is followed by a regressive systems tract. This pattern matches with the relative sea-level curves in wells McLarty 1 and Robert 1. The correlation is weak for parts of well Looma 1. This is probably influenced by the fact that the thickness of this section is quite small. As a conclusion, Fischer plots for the Llanvirnian Goldwyer and Nita Formations show good agreement with the third order global sea level cycles of Haq and others. Fischer plots are generally correlated well with trend and cyclicity determined by INPEFA curves and as a method of cross-checking INPEFA data and sea-level change.

Keywords: canning basin, Fischer plots, Llanvirnian, middle Ordovician, sea-level fluctuations, stratigraphy

Procedia PDF Downloads 260
381 Multi-Agent Searching Adaptation Using Levy Flight and Inferential Reasoning

Authors: Sagir M. Yusuf, Chris Baber

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In this paper, we describe how to achieve knowledge understanding and prediction (Situation Awareness (SA)) for multiple-agents conducting searching activity using Bayesian inferential reasoning and learning. Bayesian Belief Network was used to monitor agents' knowledge about their environment, and cases are recorded for the network training using expectation-maximisation or gradient descent algorithm. The well trained network will be used for decision making and environmental situation prediction. Forest fire searching by multiple UAVs was the use case. UAVs are tasked to explore a forest and find a fire for urgent actions by the fire wardens. The paper focused on two problems: (i) effective agents’ path planning strategy and (ii) knowledge understanding and prediction (SA). The path planning problem by inspiring animal mode of foraging using Lévy distribution augmented with Bayesian reasoning was fully described in this paper. Results proof that the Lévy flight strategy performs better than the previous fixed-pattern (e.g., parallel sweeps) approaches in terms of energy and time utilisation. We also introduced a waypoint assessment strategy called k-previous waypoints assessment. It improves the performance of the ordinary levy flight by saving agent’s resources and mission time through redundant search avoidance. The agents (UAVs) are to report their mission knowledge at the central server for interpretation and prediction purposes. Bayesian reasoning and learning were used for the SA and results proof effectiveness in different environments scenario in terms of prediction and effective knowledge representation. The prediction accuracy was measured using learning error rate, logarithm loss, and Brier score and the result proves that little agents mission that can be used for prediction within the same or different environment. Finally, we described a situation-based knowledge visualization and prediction technique for heterogeneous multi-UAV mission. While this paper proves linkage of Bayesian reasoning and learning with SA and effective searching strategy, future works is focusing on simplifying the architecture.

Keywords: Levy flight, distributed constraint optimization problem, multi-agent system, multi-robot coordination, autonomous system, swarm intelligence

Procedia PDF Downloads 117
380 Effect of Upper Face Sheet Material on Flexural Strength of Polyurethane Foam Hybrid Sandwich Material

Authors: M. Atef Gabr, M. H. Abdel Latif, Ramadan El Gamsy

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Sandwich panels comprise a thick, light-weight plastic foam such as polyurethane (PU) sandwiched between two relatively thin faces. One or both faces may be flat, lightly profiled or fully profiled. Until recently sandwich panel construction in Egypt has been widely used in cold-storage buildings, cold trucks, prefabricated buildings and insulation in construction. Recently new techniques are used in mass production of Sandwich Materials such as Reaction Injection Molding (RIM) and Vacuum bagging technique. However, in recent times their use has increased significantly due to their widespread structural applications in building systems. Structural sandwich panels generally used in Egypt comprise polyurethane foam core and thinner (0.42 mm) and high strength about 550 MPa (yield strength) flat steel faces bonded together using separate adhesives and By RIM technique. In this paper, we will use a new technique in sandwich panel preparation by using different face sheet materials in combination with polyurethane foam to form sandwich panel structures. Previously, PU Foam core with same thin 2 faces material was used, but in this work, we use different face materials and thicknesses for the upper face sheet such as Galvanized steel sheets (G.S),Aluminum sheets (Al),Fiberglass sheets (F.G) and Aluminum-Rubber composite sheets (Al/R) with polyurethane foam core 10 mm thickness and 45 Kg/m3 Density and Galvanized steel as lower face sheet. Using Aluminum-Rubber composite sheets as face sheet is considered a hybrid composite sandwich panel which is built by Hand-Layup technique by using PU glue as adhesive. This modification increases the benefits of the face sheet that will withstand different working environments with relatively small increase in its weight and will be useful in several applications. In this work, a 3-point bending test is used assistant professor to measure the most important factor in sandwich materials that is strength to weight ratio(STW) for different combinations of sandwich structures and make a comparison to study the effect of changing the face sheet material on the mechanical behavior of PU sandwich material. Also, the density of the different prepared sandwich materials will be measured to obtain the specific bending strength.

Keywords: hybrid sandwich panel, mechanical behavior, PU foam, sandwich panel, 3-point bending, flexural strength

Procedia PDF Downloads 285
379 Bond Strength of Nano Silica Concrete Subjected to Corrosive Environments

Authors: Muhammad S. El-Feky, Mohamed I. Serag, Ahmed M. Yasien, Hala Elkady

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Reinforced concrete requires steel bars in order to provide the tensile strength that is needed in structural concrete. However, when steel bars corrode, a loss in bond between the concrete and the steel bars occurs due to the formation of rust on the bars surface. Permeability of concrete is a fundamental property in perspective of the durability of concrete as it represents the ease with which water or other fluids can move through concrete, subsequently transporting corrosive agents. Nanotechnology is a standout amongst active research zones that envelops varies disciplines including construction materials. The application of nanotechnology in the corrosion protection of metal has lately gained momentum as nano scale particles have ultimate physical, chemical and physicochemical properties, which may enhance the corrosion protection in comparison to large size materials. The presented research aims to study the bond performance of concrete containing relatively high volume nano silica (up to 4.5%) exposed to corrosive conditions. This was extensively studied through tensile, bond strengths as well as the permeability of nano silica concrete. In addition micro-structural analysis was performed in order to evaluate the effect of nano silica on the properties of concrete at both; the micro and nano levels. The results revealed that by the addition of nano silica, the permeability of concrete mixes decreased significantly to reach about 50% of the control mix by the addition of 4.5% nano silica. As for the corrosion resistance, the nano silica concrete is comparatively higher resistance than ordinary concrete. Increasing Nano Silica percentage increased significantly the critical time corresponding to a metal loss (equal to 50 ϻm) which usually corresponding to the first concrete cracking due to the corrosion of reinforcement to reach about 49 years instead of 40 years as for the normal concrete. Finally, increasing nano Silica percentage increased significantly the residual bond strength of concrete after being subjected to corrosive environment. After being subjected to corrosive environment, the pullout behavior was observed for the bars embedded in all of the mixes instead of the splitting behavior that was observed before being corroded. Adding 4.5% nano silica in concrete increased the residual bond strength to reach 79% instead of 27% only as compared to control mix (0%W) before the subjection of the corrosive environment. From the conducted study we can conclude that the Nano silica proved to be a significant pore blocker material.

Keywords: bond strength, concrete, corrosion resistance, nano silica, permeability

Procedia PDF Downloads 284
378 Dimensions of Public Spaces: Feelings through Human Senses

Authors: Piyush Hajela

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The significance of public spaces is on a rise in Indian cities as a strong interaction space across cultures and community. It is a pertinent gathering space for people across age and gender, where the face keeps changing with time. A public space is directly related to the social dimension, people, comfort, safety, and security, that, it proposes to provide, as inherent qualities. The presence of these and other dimensions of space, together with related equitable environments, impart certain quality to a public space. The higher the optimum contents of these dimensions, the better the quality of public space. Public is represented by PEOPLE through society and community, and space is created by dimensions. Society contains children, women and the elderly, community is composed of social, and religious groups. These behave differently in a different setting and call for varied quality of spaces, created and generated. Public spaces are spread across a city and have more or less established their existence and prominence in a social set up. While few of them are created others are discovered by the people themselves in their constant search for desirable interactive public spaces. These are the most sought after gathering spaces that have the quality of promoting social interaction, providing free accessibility, provide desirable scale etc. The emergence of public space dates back to the times when people started forming communities, display cultures and traditions publicly, gathered for religious observations and celebrations, and address the society. Traditional cities and societies in India were feudal and orthodox in their nature and yet had public spaces. When the gathering of people at one point in a city became more frequent the point became more accessible and occupied. Baras (large courts, Chowks (public squares) and Maidans (large grounds) became well-known gathering spaces in the towns and cities. As the population grew such points grew in number, each becoming a public space in itself and with a different and definite social character. The author aims at studying the various dimensions of public spaces with which a public space has power to hold people for a significant period of time. The human senses here are note referred to as taste, sight, hearing, touch or smell, but how human senses collectively respond to when stationed in a given public space. The collectives may reflect in dimensions like comfort, safety, environment, freedom etc. Various levels of similar other responses would be studied through interviews, observations and other scientific methods for both qualitative and quantitative analysis.

Keywords: society, interaction, people, accessibility, comfort, enclosure

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377 'Sit Down, Breathe, and Feel What?' Bringing a Contemplative Intervention into a Public Urban Middle School

Authors: Lunthita M. Duthely, John T. Avella, John Ganapati Coleman

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For as many as one in three adolescents living in the United States, the adolescent years is a period of low well-being and mental health challenges—from depressive symptoms to mild to moderate psychological diagnoses. Longitudinal population health studies demonstrated that these challenges persist in young adulthood, and beyond. The positive psychology (PS) approach is a more preventative approach to well-being, which contrasts the traditional, deficits approach to curing mental illness. The research among adult populations formed the basis for PS studies among adolescents. The empirical evidence for the effectiveness of PS interventions exists for both adult and youth populations. Positive Psychology interventions target individuals’ strengths, such as hope and optimism, and positive emotions, such as gratitude. Positive psychology interventions such as increasing gratitude, proved effective in many outcomes among youth, including psychological, social, and academically-related outcomes. Although gratitude-inducing studies have been conducted for the past decade in the United States, few studies have been conducted among samples of urban youth, particularly youth of diverse cultural backgrounds. For nearly two decades, the secular practice of meditation has been tested among adults and more recently among youth, focused mostly among clinical samples. The field of Contemplative Sciences explores practices such as Hatha Yoga, Tai Chi, and Meditation, as preventative practices among children and adolescents. A more recent initiative is to explore Contemplative Practices in the school environment. Contemplative Practices yield a variety of positive outcomes, including academic, social, psychological, physiological, and neurological changes among children and adolescents. Again, few studies were conducted among adolescents of diverse cultural backgrounds. The purpose of this doctoral dissertation research study was to test a gratitude-meditation intervention among middle school students attending a public charter school, located in an urban region of Metropolitan Miami. The objective of this presentation is to summarize the challenges and success of bringing a positive psychology and meditation intervention into an urban middle school. Also, the most recent findings on positive psychology and meditation interventions conducted in school environments will be presented as well.

Keywords: adolescents, contemplative intervention, gratitude, secular meditation, positive psychology, school engagement, Sri Chinmoy

Procedia PDF Downloads 373
376 Evaluate Existing Mental Health Intervention Programs Tailored for International Students in China

Authors: Nargiza Nuralieva

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This meta-analysis investigates the effectiveness of mental health interventions tailored for international students in China, with a specific focus on Uzbek students and Silk Road scholarship recipients. The comprehensive literature review synthesizes existing studies, papers, and reports, evaluating the outcomes, limitations, and cultural considerations of these programs. Data selection targets mental health programs for international students, honing in on a subset analysis related to Uzbek students and Silk Road scholarship recipients. The analysis encompasses diverse outcome measures, such as reported stress levels, utilization rates of mental health services, academic performance, and more. Results reveal a consistent and statistically significant reduction in reported stress levels, emphasizing the positive impact of these interventions. Utilization rates of mental health services witness a significant increase, highlighting the accessibility and effectiveness of support. Retention rates show marked improvement, though academic performance yields mixed findings, prompting nuanced exploration. Psychological well-being, quality of life, and overall well-being exhibit substantial enhancements, aligning with the overarching goal of holistic student development. Positive outcomes are observed in increased help-seeking behavior, positive correlations with social support, and significant reductions in anxiety levels. Cultural adaptation and satisfaction with interventions both indicate positive outcomes, underscoring the effectiveness of culturally sensitive mental health support. The findings emphasize the importance of tailored mental health interventions for international students, providing novel insights into the specific needs of Uzbek students and Silk Road scholarship recipients. This research contributes to a nuanced understanding of the multifaceted impact of mental health programs on diverse student populations, offering valuable implications for the design and refinement of future interventions. As educational institutions continue to globalize, addressing the mental health needs of international students remains pivotal for fostering inclusive and supportive learning environments.

Keywords: international students, mental health interventions, cross-cultural support, silk road scholarship, meta-analysis

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375 Reconsidering the Palaeo-Environmental Reconstruction of the Wet Zone of Sri Lanka: A Zooarchaeological Perspective

Authors: Kelum N. Manamendra-Arachchi, Kalangi Rodrigo

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Bones, teeth, and shells have been acknowledged over the last two centuries as evidence of chronology, Palaeo-environment, and human activity. Faunal traces are valid evidence of past situations because they have properties that have not changed over long periods of time. Sri Lanka has been known as an Island, which has a diverse variation of prehistoric occupation among ecological zones. Defining the Paleoecology of the past societies has been an archaeological thought developed in the 1960s. It is mainly concerned with the reconstruction from available geological and biological evidence of past biota, populations, communities, landscapes, environments, and ecosystems. Sri Lanka has dealt with this subject and considerable research has been already undertaken. The fossil and material record of Sri Lanka’s Wet Zone tropical forests continues from c. 38,000–34,000 ybp. This early and persistent human fossil, technical, and cultural florescence, as well as a collection of well-preserved tropical-forest rock shelters with associated ' on-site ' Palaeoenvironmental records, makes Sri Lanka a central and unusual case study to determine the extent and strength of early human tropical forest encounters. Excavations carried out in prehistoric caves in the low country wet zone has shown that in the last 50,000 years, the temperature in the lowland rainforests has not exceeded 5 degrees. Based on Semnopithecus Priam (Gray Langur) remains unearned from wet zone prehistoric caves, it has been argued that periods of momentous climate changes during the LGM and Terminal Pleistocene/Early Holocene boundary, with a recognizable preference for semi-open ‘Intermediate’ rainforest or edges. Continuous Genus Acavus and Oligospira occupation along with uninterrupted horizontal pervasive of Canarium sp. (‘kekuna’ nut) have proven that temperatures in the lowland rain forests have not changed by at least 5 oC over the last 50,000 years. Site Catchment or Territorial analysis cannot be no longer defensible, due to time-distance based factors as well as optimal foraging theory failed as a consequences of prehistoric people were aware of the decrease in cost-benefit ratio and located sites, and generally played out a settlement strategy that minimized the ratio of energy expanded to energy produced.

Keywords: palaeo-environment, prehistory, palaeo-ecology, zooarchaeology

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374 Use of a Novel Intermittent Compression Shoe in Reducing Lower Limb Venous Stasis

Authors: Hansraj Riteesh Bookun, Cassandra Monique Hidajat

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This pilot study investigated the efficacy of a newly designed shoe which will act as an intermittent pneumatic compression device to augment venous flow in the lower limb. The aim was to assess the degree with which a wearable intermittent compression device can increase the venous flow in the popliteal vein. Background: Deep venous thrombosis and chronic venous insufficiency are relatively common problems with significant morbidity and mortality. While mechanical and chemical thromboprophylaxis measures are in place in hospital environments (in the form of TED stockings, intermittent pneumatic compression devices, analgesia, antiplatelet and anticoagulant agents), there are limited options in a community setting. Additionally, many individuals are poorly tolerant of graduated compression stockings due to the difficulty in putting them on, their constant tightness and increased associated discomfort in warm weather. These factors may hinder the management of their chronic venous insufficiency. Method: The device is lightweight, easy to wear and comfortable, with a self-contained power source. It features a Bluetooth transmitter and can be controlled with a smartphone. It is externally almost indistinguishable from a normal shoe. During activation, two bladders are inflated -one overlying the metatarsal heads and the second at the pedal arch. The resulting cyclical increase in pressure squeezes blood into the deep venous system. This will decrease periods of stasis and potentially reduce the risk of deep venous thrombosis. The shoe was fitted to 2 healthy participants and the peak systolic velocity of flow in the popliteal vein was measured during and prior to intermittent compression phases. Assessments of total flow volume were also performed. All haemodynamic assessments were performed with ultrasound by a licensed sonographer. Results: Mean peak systolic velocity of 3.5 cm/s with standard deviation of 1.3 cm/s were obtained. There was a three fold increase in mean peak systolic velocity and five fold increase in total flow volume. Conclusion: The device augments venous flow in the leg significantly. This may contribute to lowered thromboembolic risk during periods of prolonged travel or immobility. This device may also serve as an adjunct in the treatment of chronic venous insufficiency. The study will be replicated on a larger scale in a multi—centre trial.

Keywords: venous, intermittent compression, shoe, wearable device

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373 The Effects of Nano Zerovalent Iron (nZVI) and Magnesium Oxide Nanoparticles on Methane Production during Anaerobic Digestion of Waste Activated Sludge

Authors: Passkorn Khanthongthip, John T. Novak

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Many studies have been reported that the nZVI and MgO NPs were often found in waste activated sludge (WAS). However, little is known about the impact of those NPs on WAS stabilization. The aims of this study were to investigate the effects of both NPs on WAS anaerobic digestion for methane production and to examine the change of metanogenic population under those different environments using qPCR. Four dosages (2, 50, 100, and 200 mg/g-TSS) of MgO NPs were added to four different bottles containing WAS to investigate the impact of MgO NPs on methane production during WAS anaerobic digestion. The effects of nZVI on methane production during WAS anaerobic digestion were also conducted in another four bottles using the same methods described above except that the MgO NPs were replaced by nZVI. A bottle of WAS anaerobic digestion without nanoparticles addition was also operated to serve as a control. It was found that the relative amounts, compared to the control system, of methane production in each WAS anaerobic digestion bottle adding 2, 50, 100, 200 mg/gTSS MgO NPs were 98, 62, 28, and 14 %, respectively. This suggests that higher MgO NPs resulted in lower methane production. The data of batch test for the effects of corresponding released Mg2+ indicated that 50 mg/gTSS MgO NPs or higher could inhibit methane production at least 25%. Moreover, the volatile fatty acid (VFA) concentration was 328, 384, 928, 3,684, and 7,848 mg/L for the control and four WAS anaerobic digestion bottles with 2, 50, 100, 200 mg/gTSS MgO NPs addition, respectively. Higher VFA concentration could reduce pH and subsequently decrease methanogen growth, resulting in lower methane production. The relative numbers of total gene copies of methanogens analyzed from samples taken from WAS anaerobic digestion bottles were approximately 99, 68, 38, and 24 % of control for the addition of 2, 50, 100, and 200 mg/gTSS, respectively. Obviously, the more MgO NPs appeared in sludge anaerobic digestion system, the less methanogens remained. In contrast, the relative amount of methane production found in another four WAS anaerobic digestion bottles adding 2, 50, 100, and 200 mg/gTSS nZVI were 102, 128, 112, and 104 % of the control, respectively. The measurement of methanogenic population indicated that the relative content of methanogen gene copies were 101, 132, 120, and 112 % of those found in control, respectively. Additionally, the cumulative VFA was 320, 234, 308, and 330 mg/L, respectively. This reveals that nZVI addition could assist to increase methanogenic population. Higher amount of methanogen accelerated VFA degradation for greater methane production, resulting in lower VFA accumulation in digesters. Moreover, the data for effects of corresponding released Fe2+ conducted by batch tests suggest that the addition of approximately 50 mg/gTSS nZVI increased methane production by 20%. In conclusion, the presence of MgO NPs appeared to diminish the methane production during WAS anaerobic digestion. Higher MgO NPs dosages resulted in more inhibition on methane production. In contrast, nZVI addition promoted the amount of methanogenic population which facilitated methane production.

Keywords: magnesium oxide nanoparticles, methane production, methanogenic population, nano zerovalent iron

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372 Unified Coordinate System Approach for Swarm Search Algorithms in Global Information Deficit Environments

Authors: Rohit Dey, Sailendra Karra

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This paper aims at solving the problem of multi-target searching in a Global Positioning System (GPS) denied environment using swarm robots with limited sensing and communication abilities. Typically, existing swarm-based search algorithms rely on the presence of a global coordinate system (vis-à-vis, GPS) that is shared by the entire swarm which, in turn, limits its application in a real-world scenario. This can be attributed to the fact that robots in a swarm need to share information among themselves regarding their location and signal from targets to decide their future course of action but this information is only meaningful when they all share the same coordinate frame. The paper addresses this very issue by eliminating any dependency of a search algorithm on the need of a predetermined global coordinate frame by the unification of the relative coordinate of individual robots when within the communication range, therefore, making the system more robust in real scenarios. Our algorithm assumes that all the robots in the swarm are equipped with range and bearing sensors and have limited sensing range and communication abilities. Initially, every robot maintains their relative coordinate frame and follow Levy walk random exploration until they come in range with other robots. When two or more robots are within communication range, they share sensor information and their location w.r.t. their coordinate frames based on which we unify their coordinate frames. Now they can share information about the areas that were already explored, information about the surroundings, and target signal from their location to make decisions about their future movement based on the search algorithm. During the process of exploration, there can be several small groups of robots having their own coordinate systems but eventually, it is expected for all the robots to be under one global coordinate frame where they can communicate information on the exploration area following swarm search techniques. Using the proposed method, swarm-based search algorithms can work in a real-world scenario without GPS and any initial information about the size and shape of the environment. Initial simulation results show that running our modified-Particle Swarm Optimization (PSO) without global information we can still achieve the desired results that are comparable to basic PSO working with GPS. In the full paper, we plan on doing the comparison study between different strategies to unify the coordinate system and to implement them on other bio-inspired algorithms, to work in GPS denied environment.

Keywords: bio-inspired search algorithms, decentralized control, GPS denied environment, swarm robotics, target searching, unifying coordinate systems

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371 Integrated Performance Management System a Conceptual Design for PT. XYZ

Authors: Henrie Yunianto, Dermawan Wibisono

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PT. XYZ is a family business (private company) in Indonesia that provide an educational program and consultation services. Since its establishment in 2011, the company has run without any strategic management system implemented. Though the company could survive until now. The management of PT. XYZ sees the business opportunity for such product is huge, even though the targeted market is very specific (niche), the volume is large (due to large population of Indonesia) and numbers of competitors are low (now). It can be said if the product life cycle is in between ‘Introduction stage’ and ‘growth’ stage. It is observed that nowadays the new entrants (competitors) are increasing, thus PT. XYZ consider reacting in facing the intense business rivalry by conducting the business in an appropriate manner. A Performance Management System is important to be implemented in accordance with the business sustainability and growth. The framework of Performance Management System chosen is Integrated Performance Management System (IPMS). IPMS framework has the advantages of its simplicity, linkage between its business variables and indicators where the company can see the connections between all factors measured. IPMS framework consists of perspectives: (1) Business Result, (2) Internal Processes, (3) Resource Availability. Variables and indicators were examined through deep analysis of the business external and internal environments, Strength-Weakness-Opportunity-Threat (SWOT) analysis, Porter’s five forces analysis. Analytical Hierarchy Process (AHP) analysis was then used to quantify the weight of each variable/indicators. AHP is needed since in this study, PT. XYZ, the data of existing performance indicator was not available. Later, where the IPMS is implemented, the real data measured can be examined to determine the weight factor of each indicators using correlation analysis (or other methods). In this study of IPMS design for PT. XYZ, the analysis shows that with current company goals, along with the AHP methodology, the critical indicators for each perspective are: (1) Business results: Customer satisfaction and Employee satisfaction, (2) Internal process: Marketing performance, Supplier quality, Production quality, Continues improvement; (3) Resources Availability: Leadership and company culture & value, Personal Competences, Productivity. Company and/or organization require performance management system to help them in achieving their vision and mission. Company strategy will be effectively defined and addressed by using performance management system. Integrated Performance Management System (IPMS) framework and AHP analysis help us in quantifying the factors which influence the business output expected.

Keywords: analytical hierarchy process, business strategy, differentiation strategy, integrated performance management system

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370 Understanding the Influence of Social Media on Individual’s Quality of Life Perceptions

Authors: Biljana Marković

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Social networks are an integral part of our everyday lives, becoming an indispensable medium for communication in personal and business environments. New forms and ways of communication change the general mindset and significantly affect the quality of life of individuals. Quality of life is perceived as an abstract term, but often people are not aware that they directly affect the quality of their own lives, making minor but significant everyday choices and decisions. Quality of life can be defined broadly, but in the widest sense, it involves a subjective sense of satisfaction with one's life. Scientific knowledge about the impact of social networks on self-assessment of the quality of life of individuals is only just beginning to be researched. Available research indicates potential benefits as well as a number of disadvantages. In the context of the previous claims, the focus of the study conducted by the authors of this paper focuses on analyzing the impact of social networks on individual’s self-assessment of quality of life and the correlation between time spent on social networks, and the choice of content that individuals choose to share to present themselves. Moreover, it is aimed to explain how much and in what ways they critically judge the lives of others online. The research aspires to show the positive as well as negative aspects that social networks, primarily Facebook and Instagram, have on creating a picture of individuals and how they compare themselves with others. The topic of this paper is based on quantitative research conducted on a representative sample. An analysis of the results of the survey conducted online has elaborated a hypothesis which claims that content shared by individuals on social networks influences the image they create about themselves. A comparative analysis of the results obtained with the results of similar research has led to the conclusion about the synergistic influence of social networks on the feeling of the quality of life of respondents. The originality of this work is reflected in the approach of conducting research by examining attitudes about an individual's life satisfaction, the way he or she creates a picture of himself/herself through social networks, the extent to which he/she compares herself/himself with others, and what social media applications he/she uses. At the cognitive level, scientific contributions were made through the development of information concepts on quality of life, and at the methodological level through the development of an original methodology for qualitative alignment of respondents' attitudes using statistical analysis. Furthermore, at the practical level through the application of concepts in assessing the creation of self-image and the image of others through social networks.

Keywords: quality of life, social media, self image, influence of social media

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369 The Development and Change of Settlement in Tainan County (1904-2015) Using Historical Geographic Information System

Authors: Wei Ting Han, Shiann-Far Kung

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In the early time, most of the arable land is dry farming and using rainfall as water sources for irrigation in Tainan county. After the Chia-nan Irrigation System (CIS) was completed in 1930, Chia-nan Plain was more efficient allocation of limited water sources or irrigation, because of the benefit from irrigation systems, drainage systems, and land improvement projects. The problem of long-term drought, flood and salt damage in the past were also improved by CIS. The canal greatly improved the paddy field area and agricultural output, Tainan county has become one of the important agricultural producing areas in Taiwan. With the development of water conservancy facilities, affected by national policies and other factors, many agricultural communities and settlements are formed indirectly, also promoted the change of settlement patterns and internal structures. With the development of historical geographic information system (HGIS), Academia Sinica developed the WebGIS theme with the century old maps of Taiwan which is the most complete historical map of database in Taiwan. It can be used to overlay historical figures of different periods, present the timeline of the settlement change, also grasp the changes in the natural environment or social sciences and humanities, and the changes in the settlements presented by the visualized areas. This study will explore the historical development and spatial characteristics of the settlements in various areas of Tainan County. Using of large-scale areas to explore the settlement changes and spatial patterns of the entire county, through the dynamic time and space evolution from Japanese rule to the present day. Then, digitizing the settlement of different periods to perform overlay analysis by using Taiwan historical topographic maps in 1904, 1921, 1956 and 1989. Moreover, using document analysis to analyze the temporal and spatial changes of regional environment and settlement structure. In addition, the comparison analysis method is used to classify the spatial characteristics and differences between the settlements. Exploring the influence of external environments in different time and space backgrounds, such as government policies, major construction, and industrial development. This paper helps to understand the evolution of the settlement space and the internal structural changes in Tainan County.

Keywords: historical geographic information system, overlay analysis, settlement change, Tainan County

Procedia PDF Downloads 105
368 Response of Planktonic and Aggregated Bacterial Cells to Water Disinfection with Photodynamic Inactivation

Authors: Thayse Marques Passos, Brid Quilty, Mary Pryce

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The interest in developing alternative techniques to obtain safe water, free from pathogens and hazardous substances, is growing in recent times. The photodynamic inactivation of microorganisms (PDI) is a promising ecologically-friendly and multi-target approach for water disinfection. It uses visible light as an energy source combined with a photosensitiser (PS) to transfer energy/electrons to a substrate or molecular oxygen generating reactive oxygen species, which cause cidal effects towards cells. PDI has mainly been used in clinical studies and investigations on its application to disinfect water is relatively recent. The majority of studies use planktonic cells. However, in their natural environments, bacteria quite often do not occur as freely suspended cells (planktonic) but in cell aggregates that are either freely floating or attached to surfaces as biofilms. Microbes can form aggregates and biofilms as a strategy to protect them from environmental stress. As aggregates, bacteria have a better metabolic function, they communicate more efficiently, and they are more resistant to biocide compounds than their planktonic forms. Among the bacteria that are able to form aggregates are members of the genus Pseudomonas, they are a very diverse group widely distributed in the environment. Pseudomonas species can form aggregates/biofilms in water and can cause particular problems in water distribution systems. The aim of this study was to evaluate the effectiveness of photodynamic inactivation in killing a range of planktonic cells including Escherichia coli DSM 1103, Staphylococcus aureus DSM 799, Shigella sonnei DSM 5570, Salmonella enterica and Pseudomonas putida DSM 6125, and aggregating cells of Pseudomonas fluorescens DSM 50090, Pseudomonas aeruginosa PAO1. The experiments were performed in glass Petri dishes, containing the bacterial suspension and the photosensitiser, irradiated with a multi-LED (wavelengths 430nm and 660nm) for different time intervals. The responses of the cells were monitored using the pour plate technique and confocal microscopy. The study showed that bacteria belonging to Pseudomonads group tend to be more tolerant to PDI. While E. coli, S. aureus, S. sonnei and S. enterica required a dosage ranging from 39.47 J/cm2 to 59.21 J/cm2 for a 5 log reduction, Pseudomonads needed a dosage ranging from 78.94 to 118.42 J/cm2, a higher dose being required when the cells aggregated.

Keywords: bacterial aggregation, photoinactivation, Pseudomonads, water disinfection

Procedia PDF Downloads 272