Search results for: changing dynamics
Commenced in January 2007
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Edition: International
Paper Count: 4799

Search results for: changing dynamics

389 Astronomy in the Education Area: A Narrative Review

Authors: Isabella Lima Leite de Freitas

Abstract:

The importance of astronomy for humanity is unquestionable. Despite being a robust science, capable of bringing new discoveries every day and quickly increasing the ability of researchers to understand the universe more deeply, scientific research in this area can also help in various applications outside the domain of astronomy. The objective of this study was to review and conduct a descriptive analysis of published studies that presented the importance of astronomy in the area of education. A narrative review of the literature has been performed, considering the articles published in the last five years. As astronomy involves the study of physics, chemistry, biology, mathematics and technology, one of the studies evaluated presented astronomy as the gateway to science, demonstrating the presence of astronomy in 52 school curricula in 37 countries, with celestial movement the dominant content area. Another intervention study, evaluating individuals aged 4-5 years, demonstrated that the attribution of personal characteristics to cosmic bodies, in addition to the use of comprehensive astronomy concepts, favored the learning of science in preschool-age children, considering the use of practical activities of accompaniment and free drawing. Aiming to measure scientific literacy, another study developed in Turkey, motivated the authorities of this country to change the teaching materials and curriculum of secondary schools after the term “astronomy” appeared as one of the most attractive subjects for young people aged 15 to 24. There are also reports in the literature of the use of pedagogical tools, such as the representation of the Solar System on a human scale, where students can walk along the orbits of the planets while studying the laws of dynamics. The use of this tool favored the teaching of the relationship between distance, duration and speed over the period of the planets, in addition to improving the motivation and well-being of students aged 14-16. An important impact of astronomy on education was demonstrated in the study that evaluated the participation of high school students in the Astronomical Olympiads and the International Astronomy Olympiad. The study concluded that these Olympics have considerable influence on students who pursue a career in teaching or research later on, many of whom are in the area of astronomy itself. In addition, the literature indicates that the teaching of astronomy in the digital age has facilitated the availability of data for researchers, but also for the general population. This fact can increase even more the curiosity that the astronomy area has always instilled in people and promote the dissemination of knowledge on an expanded scale. Currently, astronomy has been considered an important ally in strengthening the school curricula of children, adolescents and young adults. This has been used as teaching tools, in addition to being extremely useful for scientific literacy, being increasingly used in the area of education.

Keywords: astronomy, education area, teaching, review

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388 Consequences to Financial Reporting by Implementing Sri Lanka Financial Reporting Standard 13 on Measuring the Fair Value of Financial Instruments: Evidence from Three Sri Lankan Organizations

Authors: Nayoma Ranawaka

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The demand for the high quality internationally comparable financial information has been increased than ever with the expansion of economic activities beyond its national boundaries. Thus, the necessity of converging accounting practices across the world is now continuously discussed with greater emphasis. The global convergence to International Financial Reporting Standards has been one of the main objectives of the International Accounting Standards Setting Board (IASB) since its establishment in 2001. Accordingly, Sri Lanka has adopted IFRSs in 2012. Among the other standards as a newly introduced standard by the IASB, IFRS 13 plays a pivotal role as it deals with the Fair Value Accounting (FVA). Therefore, it is valuable to obtain knowledge about the consequences of implementing IFRS 13 in Sri Lanka and compare results across nations. According to the IFRS Jurisdictional provision of Sri Lanka, Institute of Chartered Accountants of Sri Lanka has taken official steps to adopt IFRS 13 by introducing SLFRS 13 with de jure convergence. Then this study was identified the de facto convergence of the SLFRS 13 in measuring the Fair Value of Financial Instruments in the Sri Lankan context. Accordingly, the objective of this study is to explore the consequences to financial reporting by implementing SLFRS 13 on measuring the financial instruments. In order to achieve the objective of the study expert interview and in-depth interviews with the interviewees from the selected three case studies and their independent auditor were carried out using customized three different interview guides. These three cases were selected from three different industries; Banking, Manufacturing and Finance. NVivo version 10 was used to analyze the data collected through in-depth interviews. Then the content analysis was carried out and conclusions were derived based on the findings. Contribution to the knowledge by this study can be identified in different aspects. Findings of this study facilitate accounting practitioners to get an overall picture of application of fair value standard in measuring the financial instruments and to identify the challenges and barriers to the adoption process. Further, assist auditors in carrying out their audit procedures to check the level of compliance to the fair value standard in measuring the financial instruments. Moreover, this would enable foreign investors in assessing the reliability of the financial statements of their target investments as a result of SLFRS 13 in measuring the FVs of the FIs. The findings of the study could be used to open new avenues of thinking for policy formulators to provide the necessary infrastructure to eliminate disparities exists among different regulatory bodies to facilitate full convergence and thereby growth of the economy. Further, this provides insights to the dynamics of FVA implementation that are also relevant for other developing countries.

Keywords: convergence, fair value, financial instruments, IFRS 13

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387 Forced Migrants in Israel and Their Impact on the Urban Structure of Southern Neighborhoods of Tel Aviv

Authors: Arnon Medzini, Lilach Lev Ari

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Migration, the driving force behind increased urbanization, has made cities much more diverse places to live in. Nearly one-fifth of all migrants live in the world’s 20 largest cities. In many of these global cities, migrants constitute over a third of the population. Many of contemporary migrants are in fact ‘forced migrants,’ pushed from their countries of origin due to political or ethnic violence and persecution or natural disasters. During the past decade, massive numbers of labor migrants and asylum seekers have migrated from African countries to Israel via Egypt. Their motives for leaving their countries of origin include ongoing and bloody wars in the African continent as well as corruption, severe conditions of poverty and hunger, and economic and political disintegration. Most of the African migrants came to Israel from Eritrea and Sudan as they saw Israel the closest natural geographic asylum to Africa; soon they found their way to the metropolitan Tel-Aviv area. There they concentrated in poor neighborhoods located in the southern part of the city, where they live under conditions of crowding, poverty, and poor sanitation. Today around 45,000 African migrants reside in these neighborhoods, and yet there is no legal option for expelling them due to dangers they might face upon returning to their native lands. Migration of such magnitude to the weakened neighborhoods of south Tel-Aviv can lead to the destruction of physical, social and human infrastructures. The character of the neighborhoods is changing, and the local population is the main victim. These local residents must bear the brunt of the failure of both authorities and the government to handle the illegal inhabitants. The extremely crowded living conditions place a heavy burden on the dilapidated infrastructures in the weakened areas where the refugees live and increase the distress of the veteran residents of the neighborhoods. Some problems are economic and some stem from damage to the services the residents are entitled to, others from a drastic decline in their standard of living. Even the public parks no longer serve the purpose for which they were originally established—the well-being of the public and the neighborhood residents; they have become the main gathering place for the infiltrators and a center of crime and violence. Based on secondary data analysis (for example: The Israel’s Population, Immigration and Border Authority, the hotline for refugees and migrants), the objective of this presentation is to discuss the effects of forced migration to Tel Aviv on the following tensions: between the local population and the immigrants; between the local population and the state authorities, and between human rights groups vis-a-vis nationalist local organizations. We will also describe the changes which have taken place in the urban infrastructure of the city of Tel Aviv, and discuss the efficacy of various Israeli strategic trajectories when handling human problems arising in the marginal urban regions where the forced migrant population is concentrated.

Keywords: African asylum seekers, forced migrants, marginal urban regions, urban infrastructure

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386 A Transnational Feminist Analysis of the Experiences of Return Migrant Women to Kosova

Authors: Kaltrina Kusari

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Displaced populations have received increasing attention, yet the experiences of return migrants remain largely hidden within social sciences. Existing research, albeit limited, suggests that policies which impact return migrants, especially those forced to return to their home countries, do not reflect their voices. Specifically, the United Nations Hight Commissioner for Refugees has adopted repatriation as a preferred policy solution, despite research which substantiates that returning to one’s home country is neither durable nor the end of the migration cycle; as many of 80% of returnees decide to remigrate. This one-size-fits-all approach to forced displacement does not recognize the impact of intersecting identity categories on return migration, thus failing to consider how ethnicity, gender, and class, among others, shape repatriation. To address this, this qualitative study examined the repatriation experiences of return migrant women from Kosovo and the role of social workers in facilitating return. In 2015, Kosovars constituted the fourth largest group of asylum seekers in the European Union, yet 96% of them were rejected. Additionally, since 1999 Kosovo has ranked among the top 10 countries of origin for return migrants. Considering that return migration trends are impacted by global power dynamics, this study relied on a postcolonial and transnational feminist framework to contextualize the mobility of displaced peoples in terms of globalization and conceptualize migration as a gendered process. Postcolonial and feminist theories suggest that power is partly operationalized through language, thus, Critical Discourse Analysis was used as a research methodology. CDA is concerned with examining how power, language, and discourses shape social processes and relationships of dominance. Data collection included interviews with 15 return migrant women (eight ethnic minorities and seven Albanian) and 18 service providers in Kosovo. The main findings illustrate that both returnee women and service providers rely on discourses which 1) challenge the voluntariness and sustainability of repatriation; 2) construct Kosovo as inferior to EU countries; and 3) highlight the impact of patriarchy and ethnic racism on return migration. A postcolonial transnational feminist analysis demonstrates that despite Kosovars’ challenges with repatriation, European Union countries use their power to impose repatriation as a preferred solution for Kosovo’s government. These findings add to the body of existing repatriation literature and provide important implications for how return migration might be carried out, not only in Kosovo but other countries as well.

Keywords: migration, gender, repatriation, transnational feminism

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385 Lake of Neuchatel: Effect of Increasing Storm Events on Littoral Transport and Coastal Structures

Authors: Charlotte Dreger, Erik Bollaert

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This paper presents two environmentally-friendly coastal structures realized on the Lake of Neuchâtel. Both structures reflect current environmental issues of concern on the lake and have been strongly affected by extreme meteorological conditions between their period of design and their actual operational period. The Lake of Neuchatel is one of the biggest Swiss lakes and measures around 38 km in length and 8.2 km in width, for a maximum water depth of 152 m. Its particular topographical alignment, situated in between the Swiss Plateau and the Jura mountains, combines strong winds and large fetch values, resulting in significant wave heights during storm events at both north-east and south-west lake extremities. In addition, due to flooding concerns, historically, lake levels have been lowered by several meters during the Jura correction works in the 19th and 20th century. Hence, during storm events, continuous erosion of the vulnerable molasse shorelines and sand banks generate frequent and abundant littoral transport from the center of the lake to its extremities. This phenomenon does not only cause disturbances of the ecosystem, but also generates numerous problems at natural or man-made infrastructures located along the shorelines, such as reed plants, harbor entrances, canals, etc. A first example is provided at the southwestern extremity, near the city of Yverdon, where an ensemble of 11 small islands, the Iles des Vernes, have been artificially created in view of enhancing biological conditions and food availability for bird species during their migration process, replacing at the same time two larger islands that were affected by lack of morphodynamics and general vegetalization of their surfaces. The article will present the concept and dimensioning of these islands based on 2D numerical modelling, as well as the realization and follow-up campaigns. In particular, the influence of several major storm events that occurred immediately after the works will be pointed out. Second, a sediment retention dike is discussed at the northeastern extremity, at the entrance of the Canal de la Broye into the lake. This canal is heavily used for navigation and suffers from frequent and significant sedimentation at its outlet. The new coastal structure has been designed to minimize sediment deposits around the exutory of the canal into the lake, by retaining the littoral transport during storm events. The article will describe the basic assumptions used to design the dike, as well as the construction works and follow-up campaigns. Especially the huge influence of changing meteorological conditions on the littoral transport of the Lake of Neuchatel since project design ten years ago will be pointed out. Not only the intensity and frequency of storm events are increasing, but also the main wind directions alter, affecting in this way the efficiency of the coastal structure in retaining the sediments.

Keywords: meteorological evolution, sediment transport, lake of Neuchatel, numerical modelling, environmental measures

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384 Development of a Social Assistive Robot for Elderly Care

Authors: Edwin Foo, Woei Wen, Lui, Meijun Zhao, Shigeru Kuchii, Chin Sai Wong, Chung Sern Goh, Yi Hao He

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This presentation presents an elderly care and assistive social robot development work. We named this robot JOS and he is restricted to table top operation. JOS is designed to have a maximum volume of 3600 cm3 with its base restricted to 250 mm and his mission is to provide companion, assist and help the elderly. In order for JOS to accomplish his mission, he will be equipped with perception, reaction and cognition capability. His appearance will be not human like but more towards cute and approachable type. JOS will also be designed to be neutral gender. However, the robot will still have eyes, eyelid and a mouth. For his eyes and eyelids, they will be built entirely with Robotis Dynamixel AX18 motor. To realize this complex task, JOS will be also be equipped with micro-phone array, vision camera and Intel i5 NUC computer and a powered by a 12 V lithium battery that will be self-charging. His face is constructed using 1 motor each for the eyelid, 2 motors for the eyeballs, 3 motors for the neck mechanism and 1 motor for the lips movement. The vision senor will be house on JOS forehead and the microphone array will be somewhere below the mouth. For the vision system, Omron latest OKAO vision sensor is used. It is a compact and versatile sensor that is only 60mm by 40mm in size and operates with only 5V supply. In addition, OKAO vision sensor is capable of identifying the user and recognizing the expression of the user. With these functions, JOS is able to track and identify the user. If he cannot recognize the user, JOS will ask the user if he would want him to remember the user. If yes, JOS will store the user information together with the capture face image into a database. This will allow JOS to recognize the user the next time the user is with JOS. In addition, JOS is also able to interpret the mood of the user through the facial expression of the user. This will allow the robot to understand the user mood and behavior and react according. Machine learning will be later incorporated to learn the behavior of the user so as to understand the mood of the user and requirement better. For the speech system, Microsoft speech and grammar engine is used for the speech recognition. In order to use the speech engine, we need to build up a speech grammar database that captures the commonly used words by the elderly. This database is built from research journals and literature on elderly speech and also interviewing elderly what do they want to robot to assist them with. Using the result from the interview and research from journal, we are able to derive a set of common words the elderly frequently used to request for the help. It is from this set that we build up our grammar database. In situation where there is more than one person near JOS, he is able to identify the person who is talking to him through an in-house developed microphone array structure. In order to make the robot more interacting, we have also included the capability for the robot to express his emotion to the user through the facial expressions by changing the position and movement of the eyelids and mouth. All robot emotions will be in response to the user mood and request. Lastly, we are expecting to complete this phase of project and test it with elderly and also delirium patient by Feb 2015.

Keywords: social robot, vision, elderly care, machine learning

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383 Determination of Friction and Damping Coefficients of Folded Cover Mechanism Deployed by Torsion Springs

Authors: I. Yilmaz, O. Taga, F. Kosar, O. Keles

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In this study, friction and damping coefficients of folded cover mechanism were obtained in accordance with experimental studies and data. Friction and damping coefficients are the most important inputs to accomplish a mechanism analysis. Friction and damping are two objects that change the time of deployment of mechanisms and their dynamic behaviors. Though recommended friction coefficient values exist in literature, damping is differentiating feature according to mechanic systems. So the damping coefficient should be obtained from mechanism test outputs. In this study, the folded cover mechanism use torsion springs for deploying covers that are formerly close folded position. Torsion springs provide folded covers with desirable deploying time according to variable environmental conditions. To verify all design revisions with system tests will be so costly so that some decisions are taken in accordance with numerical methods. In this study, there are two folded covers required to deploy simultaneously. Scotch-yoke and crank-rod mechanisms were combined to deploy folded covers simultaneously. The mechanism was unlocked with a pyrotechnic bolt onto scotch-yoke disc. When pyrotechnic bolt was exploded, torsion springs provided rotational movement for mechanism. Quick motion camera was recording dynamic behaviors of system during deployment case. Dynamic model of mechanism was modeled as rigid body with Adams MBD (multi body dynamics) then torque values provided by torsion springs were used as an input. A well-advised range of friction and damping coefficients were defined in Adams DOE (design of experiment) then a large number of analyses were performed until deployment time of folded covers run in with test data observed in record of quick motion camera, thus the deployment time of mechanism and dynamic behaviors were obtained. Same mechanism was tested with different torsion springs and torque values then outputs were compared with numerical models. According to comparison, it was understood that friction and damping coefficients obtained in this study can be used safely when studying on folded objects required to deploy simultaneously. In addition to model generated with Adams as rigid body the finite element model of folded mechanism was generated with Abaqus then the outputs of rigid body model and finite element model was compared. Finally, the reasonable solutions were suggested about different outputs of these solution methods.

Keywords: damping, friction, pyro-technic, scotch-yoke

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382 Dynamics of Hepatitis B Infection Prevention Practices among Pregnant Women Attending Antenatal Care in Central Uganda Using the Constructs of Information-Motivation-Behavioral Skills Model: A Case of Lubaga Hospital Kampala

Authors: Ismail Bamidele Afolabi, Abdulmujeeb Babatunde Aremu, Lawal Abdurraheem Maidoki, Nnodimele Onuigbo Atulomah

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Background: Hepatitis B virus infection remains a significant global public health challenge with infectivity as well as the potential for transmission more than 50 to 100 times that of HIV. Annually, global HBV-related mortality is linked primarily to cirrhosis and liver carcinoma. The ever-increasing endemicity of HBV among children under-5-years, owing to vertical transmission and its lingering chronicity in developing countries, will hamper the global efforts concertedly endorsed towards eliminating viral hepatitis as a global public health threat by 2030. Objective: This study assessed information motivation behavioral skills model constructs as predictors of HBV infection prevention practices among consenting expectant mothers attending antenatal care in Central Uganda as a focal point of intervention towards breaking materno-foetal transmission of HBV. Methods: A cross-sectional study with a quantitative data collection approach based on the constructs of the IMB model was used to capture data on the study variables among 385 randomly selected pregnant women between September and October 2020. Data derived from the quantitative instrument were transformed into weighted aggregate scores using SPSS version 26. ANOVA and regression analysis were done to ascertain the study hypotheses with a significance level set as (p ≤ 0.05). Results: Relatively 60% of the respondents were aged between 18 and 28. Expectant mothers with secondary education (42.3%) were predominant. Furthermore, an average but inadequate knowledge (X ̅=5.97±6.61; B=0.57; p<.001), incorrect perception (X ̅=17.10±18.31; B=0.97; p=.014), and good behavioral skills (X ̅=12.39±13.37; B=0.56; p<.001) for adopting prevention practices all statistically predicted the unsatisfactory level of prevention practices (X ̅=15.03±16.20) among the study respondents as measured on rating scales of 12, 33, 21 and 30 respectively. Conclusion: Evidence from this study corroborates the imperativeness of IMB constructs in reducing the burden of HBV infection in developing countries. Therefore, the inadequate HBV knowledge and misperception among obstetric populations necessitate personalized health education during antenatal visits and subsequent health campaigns in order to inform better prevention practices and, in turn, reduce the lingering chronicity of HBV infection in developing countries.

Keywords: behavioral skills, HBV infection, knowledge, perception, pregnant women, prevention practices

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381 High-Speed Particle Image Velocimetry of the Flow around a Moving Train Model with Boundary Layer Control Elements

Authors: Alexander Buhr, Klaus Ehrenfried

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Trackside induced airflow velocities, also known as slipstream velocities, are an important criterion for the design of high-speed trains. The maximum permitted values are given by the Technical Specifications for Interoperability (TSI) and have to be checked in the approval process. For train manufactures it is of great interest to know in advance, how new train geometries would perform in TSI tests. The Reynolds number in moving model experiments is lower compared to full-scale. Especially the limited model length leads to a thinner boundary layer at the rear end. The hypothesis is that the boundary layer rolls up to characteristic flow structures in the train wake, in which the maximum flow velocities can be observed. The idea is to enlarge the boundary layer using roughness elements at the train model head so that the ratio between the boundary layer thickness and the car width at the rear end is comparable to a full-scale train. This may lead to similar flow structures in the wake and better prediction accuracy for TSI tests. In this case, the design of the roughness elements is limited by the moving model rig. Small rectangular roughness shapes are used to get a sufficient effect on the boundary layer, while the elements are robust enough to withstand the high accelerating and decelerating forces during the test runs. For this investigation, High-Speed Particle Image Velocimetry (HS-PIV) measurements on an ICE3 train model have been realized in the moving model rig of the DLR in Göttingen, the so called tunnel simulation facility Göttingen (TSG). The flow velocities within the boundary layer are analysed in a plain parallel to the ground. The height of the plane corresponds to a test position in the EN standard (TSI). Three different shapes of roughness elements are tested. The boundary layer thickness and displacement thickness as well as the momentum thickness and the form factor are calculated along the train model. Conditional sampling is used to analyse the size and dynamics of the flow structures at the time of maximum velocity in the train wake behind the train. As expected, larger roughness elements increase the boundary layer thickness and lead to larger flow velocities in the boundary layer and in the wake flow structures. The boundary layer thickness, displacement thickness and momentum thickness are increased by using larger roughness especially when applied in the height close to the measuring plane. The roughness elements also cause high fluctuations in the form factors of the boundary layer. Behind the roughness elements, the form factors rapidly are approaching toward constant values. This indicates that the boundary layer, while growing slowly along the second half of the train model, has reached a state of equilibrium.

Keywords: boundary layer, high-speed PIV, ICE3, moving train model, roughness elements

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380 Long-Term Variabilities and Tendencies in the Zonally Averaged TIMED-SABER Ozone and Temperature in the Middle Atmosphere over 10°N-15°N

Authors: Oindrila Nath, S. Sridharan

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Long-term (2002-2012) temperature and ozone measurements by Sounding of Atmosphere by Broadband Emission Radiometry (SABER) instrument onboard Thermosphere, Ionosphere, Mesosphere Energetics and Dynamics (TIMED) satellite zonally averaged over 10°N-15°N are used to study their long-term changes and their responses to solar cycle, quasi-biennial oscillation and El Nino Southern Oscillation. The region is selected to provide more accurate long-term trends and variabilities, which were not possible earlier with lidar measurements over Gadanki (13.5°N, 79.2°E), which are limited to cloud-free nights, whereas continuous data sets of SABER temperature and ozone are available. Regression analysis of temperature shows a cooling trend of 0.5K/decade in the stratosphere and that of 3K/decade in the mesosphere. Ozone shows a statistically significant decreasing trend of 1.3 ppmv per decade in the mesosphere although there is a small positive trend in stratosphere at 25 km. Other than this no significant ozone trend is observed in stratosphere. Negative ozone-QBO response (0.02ppmv/QBO), positive ozone-solar cycle (0.91ppmv/100SFU) and negative response to ENSO (0.51ppmv/SOI) have been found more in mesosphere whereas positive ozone response to ENSO (0.23ppmv/SOI) is pronounced in stratosphere (20-30 km). The temperature response to solar cycle is more positive (3.74K/100SFU) in the upper mesosphere and its response to ENSO is negative around 80 km and positive around 90-100 km and its response to QBO is insignificant at most of the heights. Composite monthly mean of ozone volume mixing ratio shows maximum values during pre-monsoon and post-monsoon season in middle stratosphere (25-30 km) and in upper mesosphere (85-95 km) around 10 ppmv. Composite monthly mean of temperature shows semi-annual variation with large values (~250-260 K) in equinox months and less values in solstice months in upper stratosphere and lower mesosphere (40-55 km) whereas the SAO becomes weaker above 55 km. The semi-annual variation again appears at 80-90 km, with large values in spring equinox and winter months. In the upper mesosphere (90-100 km), less temperature (~170-190 K) prevails in all the months except during September, when the temperature is slightly more. The height profiles of amplitudes of semi-annual and annual oscillations in ozone show maximum values of 6 ppmv and 2.5 ppmv respectively in upper mesosphere (80-100 km), whereas SAO and AO in temperature show maximum values of 5.8 K and 4.6 K in lower and middle mesosphere around 60-85 km. The phase profiles of both SAO and AO show downward progressions. These results are being compared with long-term lidar temperature measurements over Gadanki (13.5°N, 79.2°E) and the results obtained will be presented during the meeting.

Keywords: trends, QBO, solar cycle, ENSO, ozone, temperature

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379 The Politics of Identity: A Longitudinal Study of the Sociopolitical Development of Education Leaders

Authors: Shelley Zion

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This study examines the longitudinal impact (10 years) of a course for education leaders designed to encourage the development of critical consciousness surrounding issues of equity, oppression, power, and privilege. The ability to resist and challenge oppression across social and cultural contexts can be acquired through the use of transformative pedagogies that create spaces that use the practice of exploration to make connections between pervasive structural and institutional practices and race and ethnicity. This study seeks to extend this understanding by exploring the longitudinal influence of participating in a course that utilizes transformative pedagogies, course materials, exercises, and activities to encourage the practice of exploration of student experiences with racial and ethnic discrimination with the end goal of providing them with the necessary knowledge and skills that foster their ability to resist and challenge oppression and discrimination -critical action- in their lives. To this end, we use the explanatory power of the theories of critical consciousness development, sociopolitical development, and social identity construction that view exploration as a crucial practice in understanding the role ethnic and racial differences play in creating opportunities or barriers in the lives of individuals. When educators use transformative pedagogies, they create a space where students collectively explore their experiences with racial and ethnic discrimination through course readings, in-class activities, and discussions. The end goal of this exploration is twofold: first, to encourage the student’s ability to understand how differences are identified, given meaning to, and used to position them in specific places and spaces in their world; second, to scaffold students’ ability to make connections between their individual and collective differences and particular institutional and structural practices that create opportunities or barriers in their lives. Studies have found the formal exploration of students’ individual and collective differences in relation to their experiences with racial and ethnic discrimination results in developing an understanding of the roles race and ethnicity play in their lives. To trace the role played by exploration in identity construction, we utilize an integrative approach to identity construction informed by multiple theoretical frameworks grounded in cultural studies, social psychology, and sociology that understand social-cultural, racial, and ethnic -identities as dynamic and ever-changing based on context-specific environments. Stuart Hall refers to this practice as taking “symbolic detours through the past” while reflecting on the different ways individuals have been positioned based on their roots (group membership) and also how they, in turn, chose to position themselves through collective sense-making of the various meanings their differences carried through the routes they have taken. The practice of exploration in the construction of ethnic-racial identities has been found to be beneficial to sociopolitical development.

Keywords: political polarization, civic participation, democracy, education

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378 Understanding the Role of Social Entrepreneurship in Building Mobility of a Service Transportation Models

Authors: Liam Fassam, Pouria Liravi, Jacquie Bridgman

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Introduction: The way we travel is rapidly changing, car ownership and use are declining among young people and those residents in urban areas. Also, the increasing role and popularity of sharing economy companies like Uber highlight a movement towards consuming transportation solutions as a service [Mobility of a Service]. This research looks to bridge the knowledge gap that exists between city mobility, smart cities, sharing economy and social entrepreneurship business models. Understanding of this subject is crucial for smart city design, as access to affordable transport has been identified as a contributing factor to social isolation leading to issues around health and wellbeing. Methodology: To explore the current fit vis-a-vis transportation business models and social impact this research undertook a comparative analysis between a systematic literature review and a Delphi study. The systematic literature review was undertaken to gain an appreciation of the current academic thinking on ‘social entrepreneurship and smart city mobility’. The second phase of the research initiated a Delphi study across a group of 22 participants to review future opinion on ‘how social entrepreneurship can assist city mobility sharing models?’. The Delphi delivered an initial 220 results, which once cross-checked for duplication resulted in 130. These 130 answers were sent back to participants to score importance against a 5-point LIKERT scale, enabling a top 10 listing of areas for shared user transports in society to be gleaned. One further round (4) identified no change in the coefficient of variant thus no further rounds were required. Findings: Initial results of the literature review returned 1,021 journals using the search criteria ‘social entrepreneurship and smart city mobility’. Filtering allied to ‘peer review’, ‘date’, ‘region’ and ‘Chartered associated of business school’ ranking proffered a resultant journal list of 75. Of these, 58 focused on smart city design, 9 on social enterprise in cityscapes, 6 relating to smart city network design and 3 on social impact, with no journals purporting the need for social entrepreneurship to be allied to city mobility. The future inclusion factors from the Delphi expert panel indicated that smart cities needed to include shared economy models in their strategies. Furthermore, social isolation born by costs of infrastructure needed addressing through holistic A-political social enterprise models, and a better understanding of social benefit measurement is needed. Conclusion: In investigating the collaboration between key public transportation stakeholders, a theoretical model of social enterprise transportation models that positively impact upon the smart city needs of reduced transport poverty and social isolation was formed. As such, the research has identified how a revised business model of Mobility of a Service allied to a social entrepreneurship can deliver impactful measured social benefits associated to smart city design existent research.

Keywords: social enterprise, collaborative transportation, new models of ownership, transport social impact

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377 Seasonal Variability of Picoeukaryotes Community Structure Under Coastal Environmental Disturbances

Authors: Benjamin Glasner, Carlos Henriquez, Fernando Alfaro, Nicole Trefault, Santiago Andrade, Rodrigo De La Iglesia

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A central question in ecology refers to the relative importance that local-scale variables have over community composition, when compared with regional-scale variables. In coastal environments, strong seasonal abiotic influence dominates these systems, weakening the impact of other parameters like micronutrients. After the industrial revolution, micronutrients like trace metals have increased in ocean as pollutants, with strong effects upon biotic entities and biological processes in coastal regions. Coastal picoplankton communities had been characterized as a cyanobacterial dominated fraction, but in recent years the eukaryotic component of this size fraction has gained relevance due to their high influence in carbon cycle, although, diversity patterns and responses to disturbances are poorly understood. South Pacific upwelling coastal environments represent an excellent model to study seasonal changes due to a strong influence in the availability of macro- and micronutrients between seasons. In addition, some well constrained coastal bays of this region have been subjected to strong disturbances due to trace metal inputs. In this study, we aim to compare the influence of seasonality and trace metals concentrations, on the community structure of planktonic picoeukaryotes. To describe seasonal patterns in the study area, satellite data in a 6 years time series and in-situ measurements with a traditional oceanographic approach such as CTDO equipment were performed. In addition, trace metal concentrations were analyzed trough ICP-MS analysis, for the same region. For biological data collection, field campaigns were performed in 2011-2012 and the picoplankton community was described by flow cytometry and taxonomical characterization with next-generation sequencing of ribosomal genes. The relation between the abiotic and biotic components was finally determined by multivariate statistical analysis. Our data show strong seasonal fluctuations in abiotic parameters such as photosynthetic active radiation and superficial sea temperature, with a clear differentiation of seasons. However, trace metal analysis allows identifying strong differentiation within the study area, dividing it into two zones based on trace metals concentration. Biological data indicate that there are no major changes in diversity but a significant fluctuation in evenness and community structure. These changes are related mainly with regional parameters, like temperature, but by analyzing the metal influence in picoplankton community structure, we identify a differential response of some plankton taxa to metal pollution. We propose that some picoeukaryotic plankton groups respond differentially to metal inputs, by changing their nutritional status and/or requirements under disturbances as a derived outcome of toxic effects and tolerance.

Keywords: Picoeukaryotes, plankton communities, trace metals, seasonal patterns

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376 Numerical Investigation of Thermal Energy Storage Panel Using Nanoparticle Enhanced Phase Change Material for Micro-Satellites

Authors: Jelvin Tom Sebastian, Vinod Yeldho Baby

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In space, electronic devices are constantly attacked with radiation, which causes certain parts to fail or behave in unpredictable ways. To advance the thermal controllability for microsatellites, we need a new approach and thermal control system that is smaller than that on conventional satellites and that demand no electric power. Heat exchange inside the microsatellites is not that easy as conventional satellites due to the smaller size. With slight mass gain and no electric power, accommodating heat using phase change materials (PCMs) is a strong candidate for solving micro satellites' thermal difficulty. In other words, PCMs can absorb or produce heat in the form of latent heat, changing their phase and minimalizing the temperature fluctuation around the phase change point. The main restriction for these systems is thermal conductivity weakness of common PCMs. As PCM is having low thermal conductivity, it increases the melting and solidification time, which is not suitable for specific application like electronic cooling. In order to increase the thermal conductivity nanoparticles are introduced. Adding the nanoparticles in base PCM increases the thermal conductivity. Increase in weight concentration increases the thermal conductivity. This paper numerically investigates the thermal energy storage panel with nanoparticle enhanced phase change material. Silver nanostructure have increased the thermal properties of the base PCM, eicosane. Different weight concentration (1, 2, 3.5, 5, 6.5, 8, 10%) of silver enhanced phase change material was considered. Both steady state and transient analysis was performed to compare the characteristics of nanoparticle enhanced phase material at different heat loads. Results showed that in steady state, the temperature near the front panel reduced and temperature on NePCM panel increased as the weight concentration increased. With the increase in thermal conductivity more heat was absorbed into the NePCM panel. In transient analysis, it was found that the effect of nanoparticle concentration on maximum temperature of the system was reduced as the melting point of the material reduced with increase in weight concentration. But for the heat load of maximum 20W, the model with NePCM did not attain the melting point temperature. Therefore it showed that the model with NePCM is capable of holding more heat load. In order to study the heat load capacity double the load is given, maximum of 40W was given as first half of the cycle and the other is given constant OW. Higher temperature was obtained comparing the other heat load. The panel maintained a constant temperature for a long duration according to the NePCM melting point. In both the analysis, the uniformity of temperature of the TESP was shown. Using Ag-NePCM it allows maintaining a constant peak temperature near the melting point. Therefore, by altering the weight concentration of the Ag-NePCM it is possible to create an optimum operating temperature required for the effective working of the electronics components.

Keywords: carbon-fiber-reinforced polymer, micro/nano-satellite, nanoparticle phase change material, thermal energy storage

Procedia PDF Downloads 187
375 Circular Economy Initiatives in Denmark for the Recycling of Household Plastic Wastes

Authors: Rikke Lybæk

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This paper delves into the intricacies of recycling household plastic waste within Denmark, employing an exploratory case study methodology to shed light on the technical, strategic, and market dynamics of the plastic recycling value chain. Focusing on circular economy principles, the research identifies critical gaps and opportunities in recycling processes, particularly regarding plastic packaging waste derived from households, with a notable absence in food packaging reuse initiatives. The study uncovers the predominant practice of downcycling in the current value chain, underscoring a disconnect between the potential for high-quality plastic recycling and the market's readiness to embrace such materials. Through detailed examination of three leading companies in Denmark's plastic industry, the paper highlights the existing support for recycling initiatives, yet points to the necessity of assured quality in sorted plastics to foster broader adoption. The analysis further explores the importance of reuse strategies to complement recycling efforts, aiming to alleviate the pressure on virgin feedstock. The paper ventures into future perspectives, discussing different approaches such as biological degradation methods, watermark technology for plastic traceability, and the potential for bio-based and PtX plastics. These avenues promise not only to enhance recycling efficiency but also to contribute to a more sustainable circular economy by reducing reliance on virgin materials. Despite the challenges outlined, the research demonstrates a burgeoning market for recycled plastics within Denmark, propelled by both environmental considerations and customer demand. However, the study also calls for a more harmonized and effective waste collection and sorting system to elevate the quality and quantity of recyclable plastics. By casting a spotlight on successful case studies and potential technological advancements, the paper advocates for a multifaceted approach to plastic waste management, encompassing not only recycling but also innovative reuse and reduction strategies to foster a more sustainable future. In conclusion, this study underscores the urgent need for innovative, coordinated efforts in the recycling and management of plastic waste to move towards a more sustainable and circular economy in Denmark. It calls for the adoption of comprehensive strategies that include improving recycling technologies, enhancing waste collection systems, and fostering a market environment that values recycled materials, thereby contributing significantly to environmental sustainability goals.

Keywords: case study, circular economy, Denmark, plastic waste, sustainability, waste management

Procedia PDF Downloads 44
374 A Challenge to Conserve Moklen Ethnic House: Case Study in Tubpla Village, Phang Nga Province, Southern Thailand

Authors: M. Attavanich, H. Kobayashi

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Moklen is a sub-group of ethnic minority in Thailand. In the past, they were vagabonds of the sea. Their livelihood relied on the sea but they built temporary shelters to avoid strong wind and waves during monsoon season. Recently, they have permanently settled on land along coastal area and mangrove forest in Phang Nga and Phuket Province, Southern Thailand. Moklen people have their own housing culture: the Moklen ethnic house was built from local natural materials, indicating a unique structure and design. Its wooden structure is joined by rattan ropes. The construction process is very unique because of using body-based unit of measurement for design and construction. However, there are several threats for those unique structures. One of the most important threats on Moklen ethnic house is tsunami. Especially the 2004 Indian Ocean Tsunami caused widely damage to Southern Thailand and Phang Nga province was the most affected area. In that time, Moklen villages which are located along the coastal area also affected calamitously. In order to recover the damage in affected villages, mostly new modern style houses were provided by aid agencies. This process has caused a significant impact on Moklen housing culture. Not only tsunami, but also modernization has an influence on the changing appearance of the Moklen houses and the effect of modernization has been started to experience before the tsunami. As a result, local construction knowledge is very limited nowadays because the number of elderly people in Moklen has been decreasing drastically. Last but not the least, restrictions of construction materials which are originally provided from accessible mangroves, create limitations in building a Moklen house. In particular, after the Reserved Forest Act, wood chopping without any permission has become illegal. These are some of the most important reasons for Moklen ethnic houses to disappear. Nevertheless, according to the results of field surveys done in 2013 in Phang Nga province, it is found out that some Moklen ethnic houses are still available in Tubpla Village, but only a few. Next survey in the same area in 2014 showed that number of Moklen houses in the village has been started to increase significantly. That proves that there is a high potential to conserve Moklen houses. Also the project of our research team in February 2014 contributed to continuation of Moklen ethnic house. With the cooperation of the village leader and our team, it was aimed to construct a Moklen house with the help of local participants. For the project, villagers revealed the building knowledge and techniques, and in the end, project helped community to understand the value of their houses. Also, it was a good opportunity for Moklen children to learn about their culture. In addition, NGOs recently have started to support ecotourism projects in the village. It not only helps to preserve a way of life, but also contributes to preserve indigenous knowledge and techniques of Moklen ethnic house. This kind of supporting activities are important for the conservation of Moklen ethnic houses.

Keywords: conservation, construction project, Moklen Ethnic House, 2004 Indian Ocean tsunami

Procedia PDF Downloads 285
373 Sensitivity Improvement of Optical Ring Resonator for Strain Analysis with the Direction of Strain Recognition Possibility

Authors: Tayebeh Sahraeibelverdi, Ahmad Shirazi Hadi Veladi, Mazdak Radmalekshah

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Optical sensors became attractive due to preciseness, low power consumption, and intrinsic electromagnetic interference-free characteristic. Among the waveguide optical sensors, cavity-based ones attended for the high Q-factor. Micro ring resonators as a potential platform have been investigated for various applications as biosensors to pressure sensors thanks to their sensitive ring structure responding to any small change in the refractive index. Furthermore, these small micron size structures can come in an array, bringing the opportunity to have any of the resonance in a specific wavelength and be addressed in this way. Another exciting application is applying a strain to the ring and making them an optical strain gauge where the traditional ones are based on the piezoelectric material. Making them in arrays needs electrical wiring and about fifty times bigger in size. Any physical element that impacts the waveguide cross-section, Waveguide elastic-optic property change, or ring circumference can play a role. In comparison, ring size change has a larger effect than others. Here an engineered ring structure is investigated to study the strain effect on the ring resonance wavelength shift and its potential for more sensitive strain devices. At the same time, these devices can measure any strain by mounting on the surface of interest. The idea is to change the" O" shape ring to a "C" shape ring with a small opening starting from 2π/360 or one degree. We used the Mode solution of Lumbrical software to investigate the effect of changing the ring's opening and the shift induced by applied strain. The designed ring radius is a three Micron silicon on isolator ring which can be fabricated by standard complementary metal-oxide-semiconductor (CMOS) micromachining. The measured wavelength shifts from1-degree opening of the ring to a 6-degree opening have been investigated. Opening the ring for 1-degree affects the ring's quality factor from 3000 to 300, showing an order of magnitude Q-factor reduction. Assuming a strain making the ring-opening from 1 degree to 6 degrees, our simulation results showing negligible Q-factor reduction from 300 to 280. A ring resonator quality factor can reach up to 108 where an order of magnitude reduction is negligible. The resonance wavelength shift showed a blue shift and was obtained to be 1581, 1579,1578,1575nm for 1-, 2-, 4- and 6-degree ring-opening, respectively. This design can find the direction of the strain-induced by applying the opening on different parts of the ring. Moreover, by addressing the specified wavelength, we can precisely find the direction. We can open a significant opportunity to find cracks and any surface mechanical property very specifically and precisely. This idea can be implemented on polymer ring resonators while they can come with a flexible substrate and can be very sensitive to any strain making the two ends of the ring in the slit part come closer or further.

Keywords: optical ring resonator, strain gauge, strain sensor, surface mechanical property analysis

Procedia PDF Downloads 100
372 Determination of the Relative Humidity Profiles in an Internal Micro-Climate Conditioned Using Evaporative Cooling

Authors: M. Bonello, D. Micallef, S. P. Borg

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Driven by increased comfort standards, but at the same time high energy consciousness, energy-efficient space cooling has become an essential aspect of building design. Its aims are simple, aiming at providing satisfactory thermal comfort for individuals in an interior space using low energy consumption cooling systems. In this context, evaporative cooling is both an energy-efficient and an eco-friendly cooling process. In the past two decades, several academic studies have been performed to determine the resulting thermal comfort produced by an evaporative cooling system, including studies on temperature profiles, air speed profiles, effect of clothing and personnel activity. To the best knowledge of the authors, no studies have yet considered the analysis of relative humidity (RH) profiles in a space cooled using evaporative cooling. Such a study will determine the effect of different humidity levels on a person's thermal comfort and aid in the consequent improvement designs of such future systems. Under this premise, the research objective is to characterise the resulting different RH profiles in a chamber micro-climate using the evaporative cooling system in which the inlet air speed, temperature and humidity content are varied. The chamber shall be modelled using Computational Fluid Dynamics (CFD) in ANSYS Fluent. Relative humidity shall be modelled using a species transport model while the k-ε RNG formulation is the proposed turbulence model that is to be used. The model shall be validated with measurements taken using an identical test chamber in which tests are to be conducted under the different inlet conditions mentioned above, followed by the verification of the model's mesh and time step. The verified and validated model will then be used to simulate other inlet conditions which would be impractical to conduct in the actual chamber. More details of the modelling and experimental approach will be provided in the full paper The main conclusions from this work are two-fold: the micro-climatic relative humidity spatial distribution within the room is important to consider in the context of investigating comfort at occupant level; and the investigation of a human being's thermal comfort (based on Predicted Mean Vote – Predicted Percentage Dissatisfied [PMV-PPD] values) and its variation with different locations of relative humidity values. The study provides the necessary groundwork for investigating the micro-climatic RH conditions of environments cooled using evaporative cooling. Future work may also target the analysis of ways in which evaporative cooling systems may be improved to better the thermal comfort of human beings, specifically relating to the humidity content around a sedentary person.

Keywords: chamber micro-climate, evaporative cooling, relative humidity, thermal comfort

Procedia PDF Downloads 136
371 Unraveling the Evolution of Mycoplasma Hominis Through Its Genome Sequence

Authors: Boutheina Ben Abdelmoumen Mardassi, Salim Chibani, Safa Boujemaa, Amaury Vaysse, Julien Guglielmini, Elhem Yacoub

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Background and aim: Mycoplasma hominis (MH) is a pathogenic bacterium belonging to the Mollicutes class. It causes a wide range of gynecological infections and infertility among adults. Recently, we have explored for the first time the phylodistribution of Tunisian M. hominis clinical strains using an expanded MLST. We have demonstrated their distinction into two pure lineages, which each corresponding to a specific pathotype: genital infections and infertility. The aim of this project is to gain further insight into the evolutionary dynamics and the specific genetic factors that distinguish MH pathotypes Methods: Whole genome sequencing of Mycoplasma hominis clinical strains was performed using illumina Miseq. Denovo assembly was performed using a publicly available in-house pipeline. We used prokka to annotate the genomes, panaroo to generate the gene presence matrix and Jolytree to establish the phylogenetic tree. We used treeWAS to identify genetic loci associated with the pathothype of interest from the presence matrix and phylogenetic tree. Results: Our results revealed a clear categorization of the 62 MH clinical strains into two distinct genetic lineages, with each corresponding to a specific pathotype.; gynecological infections and infertility[AV1] . Genome annotation showed that GC content is ranging between 26 and 27%, which is a known characteristic of Mycoplasma genome. Housekeeping genes belonging to the core genome are highly conserved among our strains. TreeWas identified 4 virulence genes associated with the pathotype gynecological infection. encoding for asparagine--tRNA ligase, restriction endonuclease subunit S, Eco47II restriction endonuclease, and transcription regulator XRE (involved in tolerance to oxidative stress). Five genes have been identified that have a statistical association with infertility, tow lipoprotein, one hypothetical protein, a glycosyl transferase involved in capsule synthesis, and pyruvate kinase involved in biofilm formation. All strains harbored an efflux pomp that belongs to the family of multidrug resistance ABC transporter, which confers resistance to a wide range of antibiotics. Indeed many adhesion factors and lipoproteins (p120, p120', p60, p80, Vaa) have been checked and confirmed in our strains with a relatively 99 % to 96 % conserved domain and hypervariable domain that represent 1 to 4 % of the reference sequence extracted from gene bank. Conclusion: In summary, this study led to the identification of specific genetic loci associated with distinct pathotypes in M hominis.

Keywords: mycoplasma hominis, infertility, gynecological infections, virulence genes, antibiotic resistance

Procedia PDF Downloads 61
370 Crafting Robust Business Model Innovation Path with Generative Artificial Intelligence in Start-up SMEs

Authors: Ignitia Motjolopane

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Small and medium enterprises (SMEs) play an important role in economies by contributing to economic growth and employment. In the fourth industrial revolution, the convergence of technologies and the changing nature of work created pressures on economies globally. Generative artificial intelligence (AI) may support SMEs in exploring, exploiting, and transforming business models to align with their growth aspirations. SMEs' growth aspirations fall into four categories: subsistence, income, growth, and speculative. Subsistence-oriented firms focus on meeting basic financial obligations and show less motivation for business model innovation. SMEs focused on income, growth, and speculation are more likely to pursue business model innovation to support growth strategies. SMEs' strategic goals link to distinct business model innovation paths depending on whether SMEs are starting a new business, pursuing growth, or seeking profitability. Integrating generative artificial intelligence in start-up SME business model innovation enhances value creation, user-oriented innovation, and SMEs' ability to adapt to dynamic changes in the business environment. The existing literature may lack comprehensive frameworks and guidelines for effectively integrating generative AI in start-up reiterative business model innovation paths. This paper examines start-up business model innovation path with generative artificial intelligence. A theoretical approach is used to examine start-up-focused SME reiterative business model innovation path with generative AI. Articulating how generative AI may be used to support SMEs to systematically and cyclically build the business model covering most or all business model components and analyse and test the BM's viability throughout the process. As such, the paper explores generative AI usage in market exploration. Moreover, market exploration poses unique challenges for start-ups compared to established companies due to a lack of extensive customer data, sales history, and market knowledge. Furthermore, the paper examines the use of generative AI in developing and testing viable value propositions and business models. In addition, the paper looks into identifying and selecting partners with generative AI support. Selecting the right partners is crucial for start-ups and may significantly impact success. The paper will examine generative AI usage in choosing the right information technology, funding process, revenue model determination, and stress testing business models. Stress testing business models validate strong and weak points by applying scenarios and evaluating the robustness of individual business model components and the interrelation between components. Thus, the stress testing business model may address these uncertainties, as misalignment between an organisation and its environment has been recognised as the leading cause of company failure. Generative AI may be used to generate business model stress-testing scenarios. The paper is expected to make a theoretical and practical contribution to theory and approaches in crafting a robust business model innovation path with generative artificial intelligence in start-up SMEs.

Keywords: business models, innovation, generative AI, small medium enterprises

Procedia PDF Downloads 45
369 The Inverse Problem in Energy Beam Processes Using Discrete Adjoint Optimization

Authors: Aitor Bilbao, Dragos Axinte, John Billingham

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The inverse problem in Energy Beam (EB) Processes consists of defining the control parameters, in particular the 2D beam path (position and orientation of the beam as a function of time), to arrive at a prescribed solution (freeform surface). This inverse problem is well understood for conventional machining, because the cutting tool geometry is well defined and the material removal is a time independent process. In contrast, EB machining is achieved through the local interaction of a beam of particular characteristics (e.g. energy distribution), which leads to a surface-dependent removal rate. Furthermore, EB machining is a time-dependent process in which not only the beam varies with the dwell time, but any acceleration/deceleration of the machine/beam delivery system, when performing raster paths will influence the actual geometry of the surface to be generated. Two different EB processes, Abrasive Water Machining (AWJM) and Pulsed Laser Ablation (PLA), are studied. Even though they are considered as independent different technologies, both can be described as time-dependent processes. AWJM can be considered as a continuous process and the etched material depends on the feed speed of the jet at each instant during the process. On the other hand, PLA processes are usually defined as discrete systems and the total removed material is calculated by the summation of the different pulses shot during the process. The overlapping of these shots depends on the feed speed and the frequency between two consecutive shots. However, if the feed speed is sufficiently slow compared with the frequency, then consecutive shots are close enough and the behaviour can be similar to a continuous process. Using this approximation a generic continuous model can be described for both processes. The inverse problem is usually solved for this kind of process by simply controlling dwell time in proportion to the required depth of milling at each single pixel on the surface using a linear model of the process. However, this approach does not always lead to the good solution since linear models are only valid when shallow surfaces are etched. The solution of the inverse problem is improved by using a discrete adjoint optimization algorithm. Moreover, the calculation of the Jacobian matrix consumes less computation time than finite difference approaches. The influence of the dynamics of the machine on the actual movement of the jet is also important and should be taken into account. When the parameters of the controller are not known or cannot be changed, a simple approximation is used for the choice of the slope of a step profile. Several experimental tests are performed for both technologies to show the usefulness of this approach.

Keywords: abrasive waterjet machining, energy beam processes, inverse problem, pulsed laser ablation

Procedia PDF Downloads 257
368 Ahmad Sabzi Balkhkanloo, Motahareh Sadat Hashemi, Seyede Marzieh Hosseini, Saeedeh Shojaee-Aliabadi, Leila Mirmoghtadaie

Authors: Elyria Kemp, Kelly Cowart, My Bui

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According to the National Institute of Mental Health, an estimated 31.9% of adolescents have had an anxiety disorder. Several environmental factors may help to contribute to high levels of anxiety and depression in young people (i.e., Generation Z, Millennials). However, as young people negotiate life on social media, they may begin to evaluate themselves using excessively high standards and adopt self-perfectionism tendencies. Broadly defined, self-perfectionism involves very critical evaluations of the self. Perfectionism may also come from others and may manifest as socially prescribed perfectionism, and young adults are reporting higher levels of socially prescribed perfectionism than previous generations. This rising perfectionism is also associated with anxiety, greater physiological reactivity, and a sense of social disconnection. However, theories from psychology suggest that improvement in emotion regulation can contribute to enhanced psychological and emotional well-being. Emotion regulation refers to the ways people manage how and when they experience and express their emotions. Cognitive reappraisal and expressive suppression are common emotion regulation strategies. Cognitive reappraisal involves changing the meaning of a stimulus that involves construing a potentially emotion-eliciting situation in a way that changes its emotional impact. By contrast, expressive suppression involves inhibiting the behavioral expression of emotion. The purpose of this research is to examine the efficacy of social marketing initiatives which promote emotion regulation strategies to help young adults regulate their emotions. In Study 1 a single factor (emotional regulation strategy: a cognitive reappraisal, expressive, control) between-subjects design was conducted using an online, non-student consumer panel (n=96). Sixty-eight percent of participants were male, and 32% were female. Study participants belonged to the Millennial and Gen Z cohort, ranging in age from 22 to 35 (M=27). Participants were first told to spend at least three minutes writing about a public speaking appearance which made them anxious. The purpose of this exercise was to induce anxiety. Next, participants viewed one of three advertisements (randomly assigned) which promoted an emotion regulation strategy—cognitive reappraisal, expressive suppression, or an advertisement non-emotional in nature. After being exposed to one of the ads, participants responded to a measure composed of two items to access their emotional state and the efficacy of the messages in fostering emotion management. Findings indicated that individuals in the cognitive reappraisal condition (M=3.91) exhibited the most positive feelings and more effective emotion regulation than the expressive suppression (M=3.39) and control conditions (M=3.72, F(1,92) = 3.3, p<.05). Results from this research can be used by institutions (e.g., schools) in taking a leadership role in attacking anxiety and other mental health issues. Social stigmas regarding mental health can be removed and a more proactive stance can be taken in promoting healthy coping behaviors and strategies to manage negative emotions.

Keywords: emotion regulation, anxiety, social marketing, generation z

Procedia PDF Downloads 180
367 A Comparative Study of Environmental, Social and Economic Cross-Border Cooperation in Post-Conflict Environments: The Israel-Jordan Border

Authors: Tamar Arieli

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Cross-border cooperation has long been hailed as a means for stabilizing and normalizing relations between former enemies. Cooperation in problem-solving and realizing of local interests in post-conflict environments can indeed serve as a basis for developing dialogue and meaningful relations between neighbors across borders. Hence the potential for formerly sealed borders to serve as a basis for generating local and national perceptions of interdependence and as a buffer against the resume of conflict. Central questions which arise for policy-makers and third parties are how to facilitate cross-border cooperation and which areas of cooperation best serve to normalize post-conflict border regions. The Israel-Jordan border functions as a post-conflict border, in that it is a peaceful border since the 1994 Israel-Jordan peace treaty yet cross-border relations are defined but the highly securitized nature of the border region and the ongoing Arab-Israel regional conflict. This case study is based on long term qualitative research carried out in the border regions of both Israel and Jordan, which mapped and analyzed cross-border in a wide range of activities – social interactions sponsored by peace-facilitating NGOs, government sponsored agricultural cooperation, municipal initiated emergency planning in cross-border continuous urban settings, private cross-border business ventures and various environmental cooperative initiatives. These cooperative initiatives are evaluated through multiple interviews carried out with initiators and partners in cross-border cooperation as well as analysis of documentation, funding and media. These cooperative interactions are compared based on levels of cross-border local and official awareness and involvement as well as sustainability over time. This research identifies environmental cooperation as the most sustainable area of cross- border cooperation and as most conducive to generating perceptions of regional interdependence. This is a variation to the ‘New Middle East’ vision of business-based cooperation leading to conflict amelioration and regional stability. Environmental cooperation serving the public good rather than personal profit enjoys social legitimization even in the face of widespread anti-normalization sentiments common in the post-conflict environment. This insight is examined in light of philosophical and social aspects of the natural environment and its social perceptions. This research has theoretical implications for better understanding dynamics of cooperation and conflict, as well as practical ramifications for practitioners in border region policy and management.

Keywords: borders, cooperation, post-conflict, security

Procedia PDF Downloads 287
366 Inertial Spreading of Drop on Porous Surfaces

Authors: Shilpa Sahoo, Michel Louge, Anthony Reeves, Olivier Desjardins, Susan Daniel, Sadik Omowunmi

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The microgravity on the International Space Station (ISS) was exploited to study the imbibition of water into a network of hydrophilic cylindrical capillaries on time and length scales long enough to observe details hitherto inaccessible under Earth gravity. When a drop touches a porous medium, it spreads as if laid on a composite surface. The surface first behaves as a hydrophobic material, as liquid must penetrate pores filled with air. When contact is established, some of the liquid is drawn into pores by a capillarity that is resisted by viscous forces growing with length of the imbibed region. This process always begins with an inertial regime that is complicated by possible contact pinning. To study imbibition on Earth, time and distance must be shrunk to mitigate gravity-induced distortion. These small scales make it impossible to observe the inertial and pinning processes in detail. Instead, in the International Space Station (ISS), astronaut Luca Parmitano slowly extruded water spheres until they touched any of nine capillary plates. The 12mm diameter droplets were large enough for high-speed GX1050C video cameras on top and side to visualize details near individual capillaries, and long enough to observe dynamics of the entire imbibition process. To investigate the role of contact pinning, a text matrix was produced which consisted nine kinds of porous capillary plates made of gold-coated brass treated with Self-Assembled Monolayers (SAM) that fixed advancing and receding contact angles to known values. In the ISS, long-term microgravity allowed unambiguous observations of the role of contact line pinning during the inertial phase of imbibition. The high-speed videos of spreading and imbibition on the porous plates were analyzed using computer vision software to calculate the radius of the droplet contact patch with the plate and height of the droplet vs time. These observations are compared with numerical simulations and with data that we obtained at the ESA ZARM free-fall tower in Bremen with a unique mechanism producing relatively large water spheres and similarity in the results were observed. The data obtained from the ISS can be used as a benchmark for further numerical simulations in the field.

Keywords: droplet imbibition, hydrophilic surface, inertial phase, porous medium

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365 Fuels and Platform Chemicals Production from Lignocellulosic Biomass: Current Status and Future Prospects

Authors: Chandan Kundu, Sankar Bhattacharya

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A significant disadvantage of fossil fuel energy production is the considerable amount of carbon dioxide (CO₂) released, which is one of the contributors to climate change. Apart from environmental concerns, changing fossil fuel prices have pushed society gradually towards renewable energy sources in recent years. Biomass is a plentiful and renewable resource and a source of carbon. Recent years have seen increased research interest in generating fuels and chemicals from biomass. Unlike fossil-based resources, biomass is composed of lignocellulosic material, which does not contribute to the increase in atmospheric CO₂ over a longer term. These considerations contribute to the current move of the chemical industry from non-renewable feedstock to renewable biomass. This presentation focuses on generating bio-oil and two major platform chemicals that can potentially improve the environment. Thermochemical processes such as pyrolysis are considered viable methods for producing bio-oil and biomass-based platform chemicals. Fluidized bed reactors, on the other hand, are known to boost bio-oil yields during pyrolysis due to their superior mixing and heat transfer features, as well as their scalability. This review and the associated experimental work are focused on the thermochemical conversion of biomass to bio-oil and two high-value platform chemicals, Levoglucosenone (LGO) and 5-Chloromethyl furfural (5-CMF), in a fluidized bed reactor. These two active molecules with distinct features can potentially be useful monomers in the chemical and pharmaceutical industries since they are well adapted to the manufacture of biologically active products. This process took several meticulous steps. To begin, the biomass was delignified using a peracetic acid pretreatment to remove lignin. Because of its complicated structure, biomass must be pretreated to remove the lignin, increasing access to the carbohydrate components and converting them to platform chemicals. The biomass was then characterized by Thermogravimetric analysis, Synchrotron-based THz spectroscopy, and in-situ DRIFTS in the laboratory. Based on the results, a continuous-feeding fluidized bed reactor system was constructed to generate platform chemicals from pretreated biomass using hydrogen chloride acid-gas as a catalyst. The procedure also yields biochar, which has a number of potential applications, including soil remediation, wastewater treatment, electrode production, and energy resource utilization. Consequently, this research also includes a preliminary experimental evaluation of the biochar's prospective applications. The biochar obtained was evaluated for its CO₂ and steam reactivity. The outline of the presentation will comprise the following: Biomass pretreatment for effective delignification Mechanistic study of the thermal and thermochemical conversion of biomass Thermochemical conversion of untreated and pretreated biomass in the presence of an acid catalyst to produce LGO and CMF A thermo-catalytic process for the production of LGO and 5-CMF in a continuously-fed fluidized bed reactor and efficient separation of chemicals Use of biochar generated from the platform chemicals production through gasification

Keywords: biomass, pretreatment, pyrolysis, levoglucosenone

Procedia PDF Downloads 102
364 Analysis of Epileptic Electroencephalogram Using Detrended Fluctuation and Recurrence Plots

Authors: Mrinalini Ranjan, Sudheesh Chethil

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Epilepsy is a common neurological disorder characterised by the recurrence of seizures. Electroencephalogram (EEG) signals are complex biomedical signals which exhibit nonlinear and nonstationary behavior. We use two methods 1) Detrended Fluctuation Analysis (DFA) and 2) Recurrence Plots (RP) to capture this complex behavior of EEG signals. DFA considers fluctuation from local linear trends. Scale invariance of these signals is well captured in the multifractal characterisation using detrended fluctuation analysis (DFA). Analysis of long-range correlations is vital for understanding the dynamics of EEG signals. Correlation properties in the EEG signal are quantified by the calculation of a scaling exponent. We report the existence of two scaling behaviours in the epileptic EEG signals which quantify short and long-range correlations. To illustrate this, we perform DFA on extant ictal (seizure) and interictal (seizure free) datasets of different patients in different channels. We compute the short term and long scaling exponents and report a decrease in short range scaling exponent during seizure as compared to pre-seizure and a subsequent increase during post-seizure period, while the long-term scaling exponent shows an increase during seizure activity. Our calculation of long-term scaling exponent yields a value between 0.5 and 1, thus pointing to power law behaviour of long-range temporal correlations (LRTC). We perform this analysis for multiple channels and report similar behaviour. We find an increase in the long-term scaling exponent during seizure in all channels, which we attribute to an increase in persistent LRTC during seizure. The magnitude of the scaling exponent and its distribution in different channels can help in better identification of areas in brain most affected during seizure activity. The nature of epileptic seizures varies from patient-to-patient. To illustrate this, we report an increase in long-term scaling exponent for some patients which is also complemented by the recurrence plots (RP). RP is a graph that shows the time index of recurrence of a dynamical state. We perform Recurrence Quantitative analysis (RQA) and calculate RQA parameters like diagonal length, entropy, recurrence, determinism, etc. for ictal and interictal datasets. We find that the RQA parameters increase during seizure activity, indicating a transition. We observe that RQA parameters are higher during seizure period as compared to post seizure values, whereas for some patients post seizure values exceeded those during seizure. We attribute this to varying nature of seizure in different patients indicating a different route or mechanism during the transition. Our results can help in better understanding of the characterisation of epileptic EEG signals from a nonlinear analysis.

Keywords: detrended fluctuation, epilepsy, long range correlations, recurrence plots

Procedia PDF Downloads 156
363 Correlation Analysis between Sensory Processing Sensitivity (SPS), Meares-Irlen Syndrome (MIS) and Dyslexia

Authors: Kaaryn M. Cater

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Students with sensory processing sensitivity (SPS), Meares-Irlen Syndrome (MIS) and dyslexia can become overwhelmed and struggle to thrive in traditional tertiary learning environments. An estimated 50% of tertiary students who disclose learning related issues are dyslexic. This study explores the relationship between SPS, MIS and dyslexia. Baseline measures will be analysed to establish any correlation between these three minority methods of information processing. SPS is an innate sensitivity trait found in 15-20% of the population and has been identified in over 100 species of animals. Humans with SPS are referred to as Highly Sensitive People (HSP) and the measure of HSP is a 27 point self-test known as the Highly Sensitive Person Scale (HSPS). A 2016 study conducted by the author established base-line data for HSP students in a tertiary institution in New Zealand. The results of the study showed that all participating HSP students believed the knowledge of SPS to be life-changing and useful in managing life and study, in addition, they believed that all tutors and in-coming students should be given information on SPS. MIS is a visual processing and perception disorder that is found in approximately 10% of the population and has a variety of symptoms including visual fatigue, headaches and nausea. One way to ease some of these symptoms is through the use of colored lenses or overlays. Dyslexia is a complex phonological based information processing variation present in approximately 10% of the population. An estimated 50% of dyslexics are thought to have MIS. The study exploring possible correlations between these minority forms of information processing is due to begin in February 2017. An invitation will be extended to all first year students enrolled in degree programmes across all faculties and schools within the institution. An estimated 900 students will be eligible to participate in the study. Participants will be asked to complete a battery of on-line questionnaires including the Highly Sensitive Person Scale, the International Dyslexia Association adult self-assessment and the adapted Irlen indicator. All three scales have been used extensively in literature and have been validated among many populations. All participants whose score on any (or some) of the three questionnaires suggest a minority method of information processing will receive an invitation to meet with a learning advisor, and given access to counselling services if they choose. Meeting with a learning advisor is not mandatory, and some participants may choose not to receive help. Data will be collected using the Question Pro platform and base-line data will be analysed using correlation and regression analysis to identify relationships and predictors between SPS, MIS and dyslexia. This study forms part of a larger three year longitudinal study and participants will be required to complete questionnaires at annual intervals in subsequent years of the study until completion of (or withdrawal from) their degree. At these data collection points, participants will be questioned on any additional support received relating to their minority method(s) of information processing. Data from this study will be available by April 2017.

Keywords: dyslexia, highly sensitive person (HSP), Meares-Irlen Syndrome (MIS), minority forms of information processing, sensory processing sensitivity (SPS)

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362 Resolving a Piping Vibration Problem by Installing Viscous Damper Supports

Authors: Carlos Herrera Sierralta, Husain M. Muslim, Meshal T. Alsaiari, Daniel Fischer

Abstract:

Preventing piping fatigue flow induced vibration in the Oil & Gas sector demands not only the constant development of engineering design methodologies based on available software packages, but also special piping support technologies for designing safe and reliable piping systems. The vast majority of piping vibration problems in the Oil & Gas industry are provoked by the process flow characteristics which are basically intrinsically related to the fluid properties, the type of service and its different operational scenarios. In general, the corrective actions recommended for flow induced vibration in piping systems can be grouped in two major areas: those which affect the excitation mechanisms typically associated to process variables, and those which affect the response mechanism of the pipework per se, and the pipework associated steel support structure. Where possible the first option is to try to solve the flow induced problem from the excitation mechanism perspective. However, in producing facilities the approach of changing process parameters might not always be convenient as it could lead to reduction of production rates or it may require the shutdown of the system in order to perform the required piping modification. That impediment might lead to a second option, which is to modify the response of the piping system to excitation generated by the type of process flow. In principle, the action of shifting the natural frequency of the system well above the frequency inherent to the process always favours the elimination, or considerably reduces, the level of vibration experienced by the piping system. Tightening up the clearances at the supports (ideally zero gap), and adding new static supports at the system, are typical ways of increasing the natural frequency of the piping system. However, only stiffening the piping system may not be sufficient to resolve the vibration problem, and in some cases, it might not be feasible to implement it at all, as the available piping layout could create limitations on adding supports due to thermal expansion/contraction requirements. In these cases, utilization of viscous damper supports could be recommended as these devices can allow relatively large quasi-static movement of piping while providing sufficient capabilities of dissipating the vibration. Therefore, when correctly selected and installed, viscous damper supports can provide a significant effect on the response of the piping system over a wide range of frequencies. Viscous dampers cannot be used to support sustained, static loads. This paper shows over a real case example, a methodology which allows to determine the selection of the viscous damper supports via a dynamic analysis model. By implementing this methodology, it was possible to resolve the piping vibration problem throughout redesigning adequately the existing static piping supports and by adding new viscous dampers supports. This was conducted on-stream at the oil crude pipeline in question without the necessity of reducing the production of the plant. Concluding that the application of the methodology of this paper can be applied to solve similar cases in a straightforward manner.

Keywords: dynamic analysis, flow induced vibration, piping supports, turbulent flow, slug flow, viscous damper

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361 Polar Bears in Antarctica: An Analysis of Treaty Barriers

Authors: Madison Hall

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The Assisted Colonization of Polar Bears to Antarctica requires a careful analysis of treaties to understand existing legal barriers to Ursus maritimus transport and movement. An absence of land-based migration routes prevent polar bears from accessing southern polar regions on their own. This lack of access is compounded by current treaties which limit human intervention and assistance to ford these physical and legal barriers. In a time of massive planetary extinctions, Assisted Colonization posits that certain endangered species may be prime candidates for relocation to hospitable environments to which they have never previously had access. By analyzing existing treaties, this paper will examine how polar bears are limited in movement by humankind’s legal barriers. International treaties may be considered codified reflections of anthropocentric values of the best knowledge and understanding of an identified problem at a set point in time, as understood through the human lens. Even as human social values and scientific insights evolve, so too must treaties evolve which specify legal frameworks and structures impacting keystone species and related biomes. Due to costs and other myriad difficulties, only a very select number of species will be given this opportunity. While some species move into new regions and are then deemed invasive, Assisted Colonization considers that some assistance may be mandated due to the nature of humankind’s role in climate change. This moral question and ethical imperative against the backdrop of escalating climate impacts, drives the question forward; what is the potential for successfully relocating a select handful of charismatic and ecologically important life forms? Is it possible to reimagine a different, but balanced Antarctic ecosystem? Listed as a threatened species under the U.S. Endangered Species Act, a result of the ongoing loss of critical habitat by melting sea ice, polar bears have limited options for long term survival in the wild. Our current regime for safeguarding animals facing extinction frequently utilizes zoos and their breeding programs, to keep alive the genetic diversity of the species until some future time when reintroduction, somewhere, may be attempted. By exploring the potential for polar bears to be relocated to Antarctica, we must analyze the complex ethical, legal, political, financial, and biological realms, which are the backdrop to framing all questions in this arena. Can we do it? Should we do it? By utilizing an environmental ethics perspective, we propose that the Ecological Commons of the Arctic and Antarctic should not be viewed solely through the lens of human resource management needs. From this perspective, polar bears do not need our permission, they need our assistance. Antarctica therefore represents a second, if imperfect chance, to buy time for polar bears, in a world where polar regimes, not yet fully understood, are themselves quickly changing as a result of climate change.

Keywords: polar bear, climate change, environmental ethics, Arctic, Antarctica, assisted colonization, treaty

Procedia PDF Downloads 385
360 Development of Academic Software for Medial Axis Determination of Porous Media from High-Resolution X-Ray Microtomography Data

Authors: S. Jurado, E. Pazmino

Abstract:

Determination of the medial axis of a porous media sample is a non-trivial problem of interest for several disciplines, e.g., hydrology, fluid dynamics, contaminant transport, filtration, oil extraction, etc. However, the computational tools available for researchers are limited and restricted. The primary aim of this work was to develop a series of algorithms to extract porosity, medial axis structure, and pore-throat size distributions from porous media domains. A complementary objective was to provide the algorithms as free computational software available to the academic community comprising researchers and students interested in 3D data processing. The burn algorithm was tested on porous media data obtained from High-Resolution X-Ray Microtomography (HRXMT) and idealized computer-generated domains. The real data and idealized domains were discretized in voxels domains of 550³ elements and binarized to denote solid and void regions to determine porosity. Subsequently, the algorithm identifies the layer of void voxels next to the solid boundaries. An iterative process removes or 'burns' void voxels in sequence of layer by layer until all the void space is characterized. Multiples strategies were tested to optimize the execution time and use of computer memory, i.e., segmentation of the overall domain in subdomains, vectorization of operations, and extraction of single burn layer data during the iterative process. The medial axis determination was conducted identifying regions where burnt layers collide. The final medial axis structure was refined to avoid concave-grain effects and utilized to determine the pore throat size distribution. A graphic user interface software was developed to encompass all these algorithms, including the generation of idealized porous media domains. The software allows input of HRXMT data to calculate porosity, medial axis, and pore-throat size distribution and provide output in tabular and graphical formats. Preliminary tests of the software developed during this study achieved medial axis, pore-throat size distribution and porosity determination of 100³, 320³ and 550³ voxel porous media domains in 2, 22, and 45 minutes, respectively in a personal computer (Intel i7 processor, 16Gb RAM). These results indicate that the software is a practical and accessible tool in postprocessing HRXMT data for the academic community.

Keywords: medial axis, pore-throat distribution, porosity, porous media

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