Search results for: shift reagent
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1464

Search results for: shift reagent

144 De-Securitizing Identity: Narrative (In)Consistency in Periods of Transition

Authors: Katerina Antoniou

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When examining conflicts around the world, it is evident that the majority of intractable conflicts are steeped in identity. Identity seems to be not only a causal variable for conflict, but also a catalytic parameter for the process of reconciliation that follows ceasefire. This paper focuses on the process of identity securitization that occurs between rival groups of heterogeneous collective identities – ethnic, national or religious – as well as on the relationship between identity securitization and the ability of the groups involved to reconcile. Are securitized identities obstacles to the process of reconciliation, able to hinder any prospects of peace? If the level to which an identity is securitized is catalytic to a conflict’s discourse and settlement, then which factors act as indicators of identity de-securitization? The level of an in-group’s identity securitization can be estimated through a number of indicators, one of which is narrative. The stories, views and stances each in-group adopts in relation to its history of conflict and relation with their rival out-group can clarify whether that specific in-group feels victimized and threatened or safe and ready to reconcile. Accordingly, this study discusses identity securitization through narrative in relation to intractable conflicts. Are there conflicts around the world that, despite having been identified as intractable, stagnated or insoluble, show signs of identity de-securitization through narrative? This inquiry uses the case of the Cyprus conflict and its partitioned societies to present official narratives from the two communities and assess whether these narratives have transformed, indicating a less securitized in-group identity for the Greek and Turkish Cypriots. Specifically, the study compares the official historical overviews presented by each community’s Ministry of Foreign Affairs website and discusses the extent to which the two official narratives present a securitized collective identity. In addition, the study will observe whether official stances by the two communities – as adopted by community leaders – have transformed to depict less securitization over time. Additionally, the leaders’ reflection of popular opinion is evaluated through recent opinion polls from each community. Cyprus is currently experiencing renewed optimism for reunification, with the leaders of its two communities engaging in rigorous negotiations, and with rumors calling for a potential referendum for reunification to be taking place even as early as within 2016. Although leaders’ have shown a shift in their rhetoric and have moved away from narratives of victimization, this is not the case for the official narratives used by their respective ministries of foreign affairs. The study’s findings explore whether this narrative inconsistency proves that Cyprus is transitioning towards reunification, or whether the leaders are risking sending a securitized population to the polls to reject a potential reunification. More broadly, this study suggests that in the event that intractable conflicts might be moving towards viable peace, in-group narratives--official narratives in particular--can act as indicators of the extent to which rival entities have managed to reconcile.

Keywords: conflict, identity, narrative, reconciliation

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143 Cities Under Pressure: Unraveling Urban Resilience Challenges

Authors: Sherine S. Aly, Fahd A. Hemeida, Mohamed A. Elshamy

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In the face of rapid urbanization and the myriad challenges posed by climate change, population growth, and socio-economic disparities, fostering urban resilience has become paramount. This abstract offers a comprehensive overview of the study on "Urban Resilience Challenges," exploring the background, methodologies, major findings, and concluding insights. The paper unveils a spectrum of challenges encompassing environmental stressors and deep-seated socio-economic issues, such as unequal access to resources and opportunities. Emphasizing their interconnected nature, the study underscores the imperative for holistic and integrated approaches to urban resilience, recognizing the intricate web of factors shaping the urban landscape. Urbanization has witnessed an unprecedented surge, transforming cities into dynamic and complex entities. With this growth, however, comes an array of challenges that threaten the sustainability and resilience of urban environments. This study seeks to unravel the multifaceted urban resilience challenges, exploring their origins and implications for contemporary cities. Cities serve as hubs of economic, social, and cultural activities, attracting diverse populations seeking opportunities and a higher quality of life. However, the urban fabric is increasingly strained by climate-related events, infrastructure vulnerabilities, and social inequalities. Understanding the nuances of these challenges is crucial for developing strategies that enhance urban resilience and ensure the longevity of cities as vibrant and adaptive entities. This paper endeavors to discern strategic guidelines for enhancing urban resilience amidst the dynamic challenges posed by rapid urbanization. The study aims to distill actionable insights that can inform strategic approaches. Guiding the formulation of effective strategies to fortify cities against multifaceted pressures. The study employs a multifaceted approach to dissect urban resilience challenges. A qualitative method will be employed, including comprehensive literature reviews and data analysis of urban vulnerabilities that provided valuable insights into the lived experiences of resilience challenges in diverse urban settings. In conclusion, this study underscores the urgency of addressing urban resilience challenges to ensure the sustained vitality of cities worldwide. The interconnected nature of these challenges necessitates a paradigm shift in urban planning and governance. By adopting holistic strategies that integrate environmental, social, and economic considerations, cities can navigate the complexities of the 21st century. The findings provide a roadmap for policymakers, planners, and communities to collaboratively forge resilient urban futures that withstand the challenges of an ever-evolving urban landscape.

Keywords: resilient principles, risk management, sustainable cities, urban resilience

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142 Urban Planning Patterns after (COVID-19): An Assessment toward Resiliency

Authors: Mohammed AL-Hasani

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The Pandemic COVID-19 altered the daily habits and affected the functional performance of the cities after this crisis leaving remarkable impacts on many metropolises worldwide. It is so obvious that having more densification in the city leads to more threats altering this main approach that was called for achieving sustainable development. The main goal to achieve resiliency in the cities, especially in forcing risks, is to deal with a planning system that is able to resist, absorb, accommodate and recover from the impacts that had been affected. Many Cities in London, Wuhan, New York, and others worldwide carried different planning approaches and varied in reaction to safeguard the impacts of the pandemic. The cities globally varied from the radiant pattern predicted by Le Corbusier, or having multi urban centers more like the approach of Frank Lloyd Wright’s Broadacre City, or having linear growth or gridiron expansion that was common by Doxiadis, compact pattern, and many other hygiene patterns. These urban patterns shape the spatial distribution and Identify both open and natural spaces with gentrified and gentrifying areas. This crisis paid attention to reassess many planning approaches and examine the existing urban patterns focusing more on the aim of continuity and resiliency in managing the crises within the rapid transformation and the power of market forces. According to that, this paper hypothesized that those urban planning patterns determine the method of reaction in assuring quarantine for the inhabitance and the performance of public services and need to be updated through carrying out an innovative urban management system and adopt further resilience patterns in prospective urban planning approaches. This paper investigates the adaptivity and resiliency of variant urban planning patterns regarding selected cities worldwide that affected by COVID-19 and their role in applying certain management strategies in controlling the pandemic spread, finding out the main potentials that should be included in prospective planning approaches. The examination encompasses the spatial arrangement, blocks definition, plots arrangement, and urban space typologies. This paper aims to investigate the urban patterns to deliberate also the debate between densification as one of the more sustainable planning approaches and disaggregation tendency that was followed after the pandemic by restructuring and managing its application according to the assessment of the spatial distribution and urban patterns. The biggest long-term threat to dense cities proves the need to shift to online working and telecommuting, creating a mixture between using cyber and urban spaces to remobilize the city. Reassessing spatial design and growth, open spaces, urban population density, and public awareness are the main solutions that should be carried out to face the outbreak in our current cities that should be managed from global to tertiary levels and could develop criteria for designing the prospective cities

Keywords: COVID-19, densification, resiliency, urban patterns

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141 The Sustained Utility of Japan's Human Security Policy

Authors: Maria Thaemar Tana

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The paper examines the policy and practice of Japan’s human security. Specifically, it asks the question: How does Japan’s shift towards a more proactive defence posture affect the place of human security in its foreign policy agenda? Corollary to this, how is Japan sustaining its human security policy? The objective of this research is to understand how Japan, chiefly through the Ministry of Foreign Affairs (MOFA) and JICA (Japan International Cooperation Agency), sustains the concept of human security as a policy framework. In addition, the paper also aims to show how and why Japan continues to include the concept in its overall foreign policy agenda. In light of the recent developments in Japan’s security policy, which essentially result from the changing security environment, human security appears to be gradually losing relevance. The paper, however, argues that despite the strategic challenges Japan faced and is facing, as well as the apparent decline of its economic diplomacy, human security remains to be an area of critical importance for Japanese foreign policy. In fact, as Japan becomes more proactive in its international affairs, the strategic value of human security also increases. Human security was initially envisioned to help Japan compensate for its weaknesses in the areas of traditional security, but as Japan moves closer to a more activist foreign policy, the soft policy of human security complements its hard security policies. Using the framework of neoclassical realism (NCR), the paper recognizes that policy-making is essentially a convergence of incentives and constraints at the international and domestic levels. The theory posits that there is no perfect 'transmission belt' linking material power on the one hand, and actual foreign policy on the other. State behavior is influenced by both international- and domestic-level variables, but while systemic pressures and incentives determine the general direction of foreign policy, they are not strong enough to affect the exact details of state conduct. Internal factors such as leaders’ perceptions, domestic institutions, and domestic norms, serve as intervening variables between the international system and foreign policy. Thus, applied to this study, Japan’s sustained utilization of human security as a foreign policy instrument (dependent variable) is essentially a result of systemic pressures (indirectly) (independent variables) and domestic processes (directly) (intervening variables). Two cases of Japan’s human security practice in two regions are examined in two time periods: Iraq in the Middle East (2001-2010) and South Sudan in Africa (2011-2017). The cases show that despite the different motives behind Japan’s decision to participate in these international peacekeepings ad peace-building operations, human security continues to be incorporated in both rhetoric and practice, thus demonstrating that it was and remains to be an important diplomatic tool. Different variables at the international and domestic levels will be examined to understand how the interaction among them results in changes and continuities in Japan’s human security policy.

Keywords: human security, foreign policy, neoclassical realism, peace-building

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140 De-Densifying Congested Cores of Cities and Their Emerging Design Opportunities

Authors: Faith Abdul Rasak Asharaf

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Every city has a threshold known as urban carrying capacity based on which it can withstand a particular density of people, above which the city might need to resort to measures like expanding its boundaries or growing vertically. As a result of this circumstance, the number of squatter communities is growing, as is the claustrophobic feeling of being confined inside a "concrete jungle." The expansion of suburbs, commercial areas, and industrial real estate in the areas surrounding medium-sized cities has resulted in changes to their landscapes and urban forms, as well as a systematic shift in their role in the urban hierarchy when functional endowment and connections to other territories are considered. The urban carrying capacity idea provides crucial guidance for city administrators and planners in better managing, designing, planning, constructing, and distributing urban resources to satisfy the huge demands of an evergrowing urban population. An ecological footprint is a criterion of urban carrying capacity, which is the amount of land required to provide humanity with renewable resources and absorb its trash. However, as each piece of land has its unique carrying capacity, including ecological, social, and economic considerations, these metropolitan areas begin to reach a saturation point over time. Various city models have been tried throughout the years to meet the increasing urban population density by moving the zones of work, life, and leisure to achieve maximum sustainable growth. The current scenario is that of a vertical city and compact city concept, in which the maximum density of people is attempted to fit into a definite area using efficient land use and a variety of other strategies, but this has proven to be a very unsustainable method of growth, as evidenced by the COVID-19 period. Due to a shortage of housing and basic infrastructure, densely populated cities gave rise to massive squatter communities, unable to accommodate the overflowing migrants. To achieve optimum carrying capacity, planning measures such as polycentric city and diffuse city concepts can be implemented, which will help to relieve the congested city core by relocating certain sectors of the town to the city periphery, which will help to create newer spaces for design in terms of public space, transportation, and housing, which is a major concern in the current scenario. The study's goal is focused on suggesting design options and solutions in terms of placemaking for better urban quality and urban life for the citizens once city centres have been de-densified based on urban carrying capacity and ecological footprint, taking the case of Kochi as an apt example of a highly densified city core, focusing on Edappally, which is an agglomeration of many urban factors.

Keywords: urban carrying capacity, urbanization, urban sprawl, ecological footprint

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139 The Use of Emerging Technologies in Higher Education Institutions: A Case of Nelson Mandela University, South Africa

Authors: Ayanda P. Deliwe, Storm B. Watson

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The COVID-19 pandemic has disrupted the established practices of higher education institutions (HEIs). Most higher education institutions worldwide had to shift from traditional face-to-face to online learning. The online environment and new online tools are disrupting the way in which higher education is presented. Furthermore, the structures of higher education institutions have been impacted by rapid advancements in information and communication technologies. Emerging technologies should not be viewed in a negative light because, as opposed to the traditional curriculum that worked to create productive and efficient researchers, emerging technologies encourage creativity and innovation. Therefore, using technology together with traditional means will enhance teaching and learning. Emerging technologies in higher education not only change the experience of students, lecturers, and the content, but it is also influencing the attraction and retention of students. Higher education institutions are under immense pressure because not only are they competing locally and nationally, but emerging technologies also expand the competition internationally. Emerging technologies have eliminated border barriers, allowing students to study in the country of their choice regardless of where they are in the world. Higher education institutions are becoming indifferent as technology is finding its way into the lecture room day by day. Academics need to utilise technology at their disposal if they want to get through to their students. Academics are now competing for students' attention with social media platforms such as WhatsApp, Snapchat, Instagram, Facebook, TikTok, and others. This is posing a significant challenge to higher education institutions. It is, therefore, critical to pay attention to emerging technologies in order to see how they can be incorporated into the classroom in order to improve educational quality while remaining relevant in the work industry. This study aims to understand how emerging technologies have been utilised at Nelson Mandela University in presenting teaching and learning activities since April 2020. The primary objective of this study is to analyse how academics are incorporating emerging technologies in their teaching and learning activities. This primary objective was achieved by conducting a literature review on clarifying and conceptualising the emerging technologies being utilised by higher education institutions, reviewing and analysing the use of emerging technologies, and will further be investigated through an empirical analysis of the use of emerging technologies at Nelson Mandela University. Findings from the literature review revealed that emerging technology is impacting several key areas in higher education institutions, such as the attraction and retention of students, enhancement of teaching and learning, increase in global competition, elimination of border barriers, and highlighting the digital divide. The literature review further identified that learning management systems, open educational resources, learning analytics, and artificial intelligence are the most prevalent emerging technologies being used in higher education institutions. The identified emerging technologies will be further analysed through an empirical analysis to identify how they are being utilised at Nelson Mandela University.

Keywords: artificial intelligence, emerging technologies, learning analytics, learner management systems, open educational resources

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138 Targeting Glucocorticoid Receptor Eliminate Dormant Chemoresistant Cancer Stem Cells in Glioblastoma

Authors: Aoxue Yang, Weili Tian, Haikun Liu

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Brain tumor stem cells (BTSCs) are resistant to therapy and give rise to recurrent tumors. These rare and elusive cells are likely to disseminate during cancer progression, and some may enter dormancy, remaining viable but not increasing. The identification of dormant BTSCs is thus necessary to design effective therapies for glioblastoma (GBM) patients. Glucocorticoids (GCs) are used to treat GBM-associated edema. However, glucocorticoids participate in the physiological response to psychosocial stress, linked to poor cancer prognosis. This raises concern that glucocorticoids affect the tumor and BTSCs. Identifying markers specifically expressed by brain tumor stem cells (BTSCs) may enable specific therapies that spare their regular tissue-resident counterparts. By ribosome profiling analysis, we have identified that glycerol-3-phosphate dehydrogenase 1 (GPD1) is expressed by dormant BTSCs but not by NSCs. Through different stress-induced experiments in vitro, we found that only dexamethasone (DEXA) can significantly increase the expression of GPD1 in NSCs. Adversely, mifepristone (MIFE) which is classified as glucocorticoid receptors antagonists, could decrease GPD1 protein level and weaken the proliferation and stemness in BTSCs. Furthermore, DEXA can induce GPD1 expression in tumor-bearing mice brains and shorten animal survival, whereas MIFE has a distinct adverse effect that prolonged mice lifespan. Knocking out GR in NSC can block the upregulation of GPD1 inducing by DEXA, and we find the specific sequences on GPD1 promotor combined with GR, thus improving the efficiency of GPD1 transcription from CHIP-Seq. Moreover, GR and GPD1 are highly co-stained on GBM sections obtained from patients and mice. All these findings confirmed that GR could regulate GPD1 and loss of GPD1 Impairs Multiple Pathways Important for BTSCs Maintenance GPD1 is also a critical enzyme regulating glycolysis and lipid synthesis. We observed that DEXA and MIFE could change the metabolic profiles of BTSCs by regulating GPD1 to shift the transition of cell dormancy. Our transcriptome and lipidomics analysis demonstrated that cell cycle signaling and phosphoglycerides synthesis pathways contributed a lot to the inhibition of GPD1 caused by MIFE. In conclusion, our findings raise concern that treatment of GBM with GCs may compromise the efficacy of chemotherapy and contribute to BTSC dormancy. Inhibition of GR can dramatically reduce GPD1 and extend the survival duration of GBM-bearing mice. The molecular link between GPD1 and GR may give us an attractive therapeutic target for glioblastoma.

Keywords: cancer stem cell, dormancy, glioblastoma, glycerol-3-phosphate dehydrogenase 1, glucocorticoid receptor, dexamethasone, RNA-sequencing, phosphoglycerides

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137 A Comparative Human Rights Analysis of Expulsion as a Counterterrorism Instrument: An Evaluation of Belgium

Authors: Louise Reyntjens

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Where criminal law used to be the traditional response to cope with the terrorist threat, European governments are increasingly relying on administrative paths. The reliance on immigration law fits into this trend. Terrorism is seen as a civilization menace emanating from abroad. In this context, the expulsion of dangerous aliens, immigration law’s core task, is put forward as a key security tool. Governments all over Europe are focusing on removing dangerous individuals from their territory rather than bringing them to justice. This research reflects on the consequences for the expelled individuals’ fundamental rights. For this, the author selected four European countries for a comparative study: Belgium, France, the United Kingdom and Sweden. All these countries face similar social and security issues, igniting the recourse to immigration law as a counterterrorism tool. Yet, they adopt a very different approach on this: the United Kingdom positions itself on the repressive side of the spectrum. Sweden on the other hand, also 'securitized' its immigration policy after the recent terrorist hit in Stockholm, but remains on the tolerant side of the spectrum. Belgium and France are situated in between. This paper addresses the situation in Belgium. In 2017, the Belgian parliament introduced several legislative changes by which it considerably expanded and facilitated the possibility to expel unwanted aliens. First, the expulsion measure was subjected to new and questionably definitions: a serious attack on the nation’s safety used to be required to expel certain categories of aliens. Presently, mere suspicions suffice to fulfil the new definition of a 'serious threat to national security'. A definition which fails to respond to the principle of legality; the law, nor the prepatory works clarify what is meant by 'a threat to national security'. This creates the risk of submitting this concept’s interpretation almost entirely to the discretion of the immigration authorities. Secondly, in name of intervening more quickly and efficiently, the automatic suspensive appeal for expulsions was abolished. The European Court of Human Rights nonetheless requires such an automatic suspensive appeal under Article 13 and 3 of the Convention. Whether this procedural reform will stand to endure, is thus questionable. This contribution also raises questions regarding expulsion’s efficacy as a key security tool. In a globalized and mobilized world, particularly in a European Union with no internal boundaries, questions can be raised about the usefulness of this measure. Even more so, by simply expelling a dangerous individual, States avoid their responsibility and shift the risk to another State. Criminal law might in these instances be more capable of providing a conclusive and long term response. This contribution explores the human rights consequences of expulsion as a security tool in Belgium. It also offers a critical view on its efficacy for protecting national security.

Keywords: Belgium, counter-terrorism and human rights, expulsion, immigration law

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136 A Density Function Theory Based Comparative Study of Trans and Cis - Resveratrol

Authors: Subhojyoti Chatterjee, Peter J. Mahon, Feng Wang

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Resveratrol (RvL), a phenolic compound, is a key ingredient in wine and tomatoes that has been studied over the years because of its important bioactivities such as anti-oxidant, anti-aging and antimicrobial properties. Out of the two isomeric forms of resveratrol i.e. trans and cis, the health benefit is primarily associated with the trans form. Thus, studying the structural properties of the isomers will not only provide an insight into understanding the RvL isomers, but will also help in designing parameters for differentiation in order to achieve 99.9% purity of trans-RvL. In the present study, density function theory (DFT) study is conducted, using the B3LYP/6-311++G** model to explore the through bond and through space intramolecular interactions. Properties such as vibrational spectroscopy (IR and Raman), nuclear magnetic resonance (NMR) spectra, excess orbital energy spectrum (EOES), energy based decomposition analyses (EDA) and Fukui function are calculated. It is discovered that the structure of trans-RvL, although it is C1 non-planar, the backbone non-H atoms are nearly in the same plane; whereas the cis-RvL consists of two major planes of R1 and R2 that are not in the same plane. The absence of planarity gives rise to a H-bond of 2.67Å in cis-RvL. Rotation of the C(5)-C(8) single bond in trans-RvL produces higher energy barriers since it may break the (planar) entire conjugated structure; while such rotation in cis-RvL produces multiple minima and maxima depending on the positions of the rings. The calculated FT-IR spectrum shows very different spectral features for trans and cis-RvL in the region 900 – 1500 cm-1, where the spectral peaks at 1138-1158 cm-1 are split in cis-RvL compared to a single peak at 1165 cm-1 in trans-RvL. In the Raman spectra, there is significant enhancement of cis-RvL in the region above 3000cm-1. Further, the carbon chemical environment (13C NMR) of the RvL molecule exhibit a larger chemical shift for cis-RvL compared to trans-RvL (Δδ = 8.18 ppm) for the carbon atom C(11), indicating that the chemical environment of the C group in cis-RvL is more diverse than its other isomer. The energy gap between highest occupied molecular orbital (HOMO) and the lowest occupied molecular orbital (LUMO) is 3.95 eV for trans and 4.35 eV for cis-RvL. A more detailed inspection using the recently developed EOES revealed that most of the large energy differences i.e. Δεcis-trans > ±0.30 eV, in their orbitals are contributed from the outer valence shell. They are MO60 (HOMO), MO52-55 and MO46. The active sites that has been captured by Fukui function (f + > 0.08) are associated with the stilbene C=C bond of RvL and cis-RvL is more active at these sites than in trans-RvL, as cis orientation breaks the large conjugation of trans-RvL so that the hydroxyl oxygen’s are more active in cis-RvL. Finally, EDA highlights the interaction energy (ΔEInt) of the phenolic compound, where trans is preferred over the cis-RvL (ΔΔEi = -4.35 kcal.mol-1) isomer. Thus, these quantum mechanics results could help in unwinding the diversified beneficial activities associated with resveratrol.

Keywords: resveratrol, FT-IR, Raman, NMR, excess orbital energy spectrum, energy decomposition analysis, Fukui function

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135 The Institutional Change Occurring in the Chinese Sport Sector: A Case Study on the Chinese Football Association Reform

Authors: Qi Peng

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The Chinese sport sector is currently undergoing a dramatic institutional change. A sport system that was heavily dominated by the government is starting to shift towards one that is driven by the market. During the past sixty years, the Chinese Football Association (CFA), although ostensibly a ‘non-governmental organization’, has been in fact operated under the close supervision and control of the government. The double-identity of CFA has taken most of the blame for the poor performance of the Chinese football team, especially the men’s team. In 2015, a policy initiated by the Chinese government introduced a potentially radical change to the institutional structure of CFA by delegating the power of government agency – the General Administration of Sport of China - to the organization (CFA) itself. Against such background, an overarching research question was brought up- will an organization remained institutionalized within the system change in response to the external (policy) jolt? To answer this question, three principal data collection methods were employed: document review, participant observation and semi-structured interviews. Document review provides the mapping of the structural and cultural framework in which the CFA functions during the change process. The author have had the chance to interact closely with the organization as participant observer in the organization for a period of time, long enough to collect the data, but never too long to get biased view of the situation. This stage enables the author to gain an in-depth understanding of how CFA managed to restructure the governance and legitimacy. Conducting semi-structured interviews with staff within the CFA and from staff within selected stakeholders of CFA also provided a crucial step to gain an insight into the factors for change as well as the implications of the change. A wide range of interviewees that have been and to be interviewed include: CFA members (senior officials and staff); local football associations members; senior Chinese Super League football club managers; CFA Super League Co., LTD (senior officials and staff); CSL broadcasters; Chinese Olympic Committee members. The preliminary research data shows that the CFA is currently undergoing two levels of change: although the settings of CFA has been gradually restructured (organizational framework), the organizational values and beliefs remain almost the same as the CFA before the reform. This means that the plan of shifting from a governmental agency to an autonomous association is an going process, and that organizational core beliefs and values are more difficult to change than its structural framework. This is due to the inertia of the organizational history and the effect of institutionalization. The change of Chinese Football Association is looked at as a pioneering sport organization in China to undertake the “decoupling” road. It is believed that many other sport organizations, especially sport governing bodies will follow the step of CFA in the near future. Therefore, the experience of CFA change is worthy of studying.

Keywords: Chinese Football Association, Organizational Change, Organizational Culture, Structural Framework

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134 Transient Heat Transfer: Experimental Investigation near the Critical Point

Authors: Andreas Kohlhepp, Gerrit Schatte, Wieland Christoph, Spliethoff Hartmut

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In recent years the research of heat transfer phenomena of water and other working fluids near the critical point experiences a growing interest for power engineering applications. To match the highly volatile characteristics of renewable energies, conventional power plants need to shift towards flexible operation. This requires speeding up the load change dynamics of steam generators and their heating surfaces near the critical point. In dynamic load transients, both a high heat flux with an unfavorable ratio to the mass flux and a high difference in fluid and wall temperatures, may cause problems. It may lead to deteriorated heat transfer (at supercritical pressures), dry-out or departure from nucleate boiling (at subcritical pressures), all cases leading to an extensive rise of temperatures. For relevant technical applications, the heat transfer coefficients need to be predicted correctly in case of transient scenarios to prevent damage to the heated surfaces (membrane walls, tube bundles or fuel rods). In transient processes, the state of the art method of calculating the heat transfer coefficients is using a multitude of different steady-state correlations for the momentarily existing local parameters for each time step. This approach does not necessarily reflect the different cases that may lead to a significant variation of the heat transfer coefficients and shows gaps in the individual ranges of validity. An algorithm was implemented to calculate the transient behavior of steam generators during load changes. It is used to assess existing correlations for transient heat transfer calculations. It is also desirable to validate the calculation using experimental data. By the use of a new full-scale supercritical thermo-hydraulic test rig, experimental data is obtained to describe the transient phenomena under dynamic boundary conditions as mentioned above and to serve for validation of transient steam generator calculations. Aiming to improve correlations for the prediction of the onset of deteriorated heat transfer in both, stationary and transient cases the test rig was specially designed for this task. It is a closed loop design with a directly electrically heated evaporation tube, the total heating power of the evaporator tube and the preheater is 1MW. To allow a big range of parameters, including supercritical pressures, the maximum pressure rating is 380 bar. The measurements contain the most important extrinsic thermo-hydraulic parameters. Moreover, a high geometric resolution allows to accurately predict the local heat transfer coefficients and fluid enthalpies.

Keywords: departure from nucleate boiling, deteriorated heat transfer, dryout, supercritical working fluid, transient operation of steam generators

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133 Knowledge, Attitude, and Practice of Physical Activity among Adults in Alimosho Local Government Area

Authors: Elizabeth Adebomi Akinlotan, Olukemi Odukoya

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INTRODUCTION: Physical Activity is defined as activity that involves bodily movement which is done as a part of daily activity in the form of working, playing, active transportation such as walking and also as a form of recreational activity. Physical inactivity has been identified as the fourth leading risk factor for global mortality and morbidity causing an estimated 3.2 million deaths globally and 5.5% of total deaths and it remains a pressing public health issue. There is a shift in the major causes of death from communicable to non-communicable diseases in many developed countries and this is fast becoming the case in developing countries. Physical activity is an important determinant of health and has been associated with lower mortality rates as it reduces the risk of developing chronic diseases such as diabetes mellitus, hypertension, stroke, cancer and osteoporosis. It improves musculoskeletal health, controls weight and reduces symptoms of depression. AIM: The aim is to study the knowledge, attitude and practices of physical activity among adults in Alimosho local government area. METHODOLOGY: This was a descriptive cross sectional survey designed to study the knowledge, attitude and practice of physical activity among adults in Alimosho Local Government Area. The study population were 250 adults aged 18-65 who were residents of the area of more than 6 months duration and had no chronic disease condition or physical disability. A multistage sampling method was used to select the respondents and data was collected using interviewer administered questionnaires. The data was analyzed with the use of EPI-info 2007 statistical software. Chi Square was thereafter used to test the association between selected variables. The level of statistical significance was set at 5% (p<0.05). RESULTS: In general, majority (61.6%) of the respondents had a good knowledge of what physical activity entails, 34.0% had fair knowledge and 4.4% had poor knowledge. There was a favorable attitude towards physical activity among the respondents with 82.4% having an overall positive attitude. Below a third of the respondents (26.4%) reported having a high physical activity (METS > 3001) while 40.0% had moderate (601-3000 METS) levels of activity and 33.6% were inactive (<600METS). There is statistical significance between the gender of the respondent and the levels of physical activity (p=0.0007); 75.2% males reached the minimum recommendations while 24.8% were inactive and 55.0% females reached the minimum recommendations while 45.0% were inactive. Results also showed that of 95 respondents who were satisfied with their levels of physical activity, 33.7% were insufficiently active while 66.3% were either minimally active or highly active and of 110 who were unsatisfied with their levels of physical activity, 72.0% were above the minimum recommendations while 38.0% were insufficiently active. CONCLUSION: In contrast to the high level of knowledge and favorable attitude towards physical activity, there was a lower level of practice of high or moderate physical activities. It is recommended that more awareness should be created on the recommended levels of physical activity especially for the vigorous intensity and moderate intensity physical activity.

Keywords: METS, physical activity, physical inactivity, public health

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132 Subtropical Potential Vorticity Intrusion Drives Increasing Tropospheric Ozone over the Tropical Central Pacific

Authors: Debashis Nath

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Drawn from multiple reanalysis datasets, an increasing trend and westward shift in the number of Potential Vorticity (PV) intrusion events over the Pacific are evident. The increased frequency can be linked to a long-term trend in upper tropospheric (UT, 200 hPa) equatorial westerly wind and subtropical jets (STJ) during boreal winter to spring. These may be resulting from anomalous warming and cooling over the western Pacific warm pool and the tropical eastern Pacific, respectively. The intrusions brought dry and ozone rich air of stratospheric origin deep into the tropics. In the tropical UT, interannual ozone variability is mainly related to convection associated with El Niño/Southern Oscillation. Zonal mean stratospheric overturning circulation organizes the transport of ozone rich air poleward and downward to the high and midlatitudes leading there to higher ozone concentration. In addition to these well described mechanisms, we observe a long-term increasing trend in ozone flux over the northern hemispheric outer tropical (10–25°N) central Pacific that results from equatorward transport and downward mixing from the midlatitude UT and lower stratosphere (LS) during PV intrusions. This increase in tropospheric ozone flux over the Pacific Ocean may affect the radiative processes and changes the budget of atmospheric hydroxyl radicals. The results demonstrate a long-term increase in outer tropical Pacific PV intrusions linked with the strengthening of the upper tropospheric equatorial westerlies and weakening of the STJ. Zonal variation in SST, characterized by gradual warming in the western Pacific–warm pool and cooling in the central–eastern Pacific, is associated with the strengthening of the Pacific Walker circulation. In the Western Pacific enhanced convective activity leads to precipitation, and the latent heat released in the process strengthens the Pacific Walker circulation. However, it is linked with the trend in global mean temperature, which is related to the emerging anthropogenic greenhouse signal and negative phase of PDO. On the other hand, the central-eastern Pacific cooling trend is linked to the weakening of the central–eastern Pacific Hadley circulation. It suppresses the convective activity due to sinking air motion and imports less angular momentum to the STJ leading to a weakened STJ. While, more PV intrusions result from this weaker STJ on its equatorward side; significantly increase the stratosphere-troposphere exchange processes on the longer timescale. This plays an important role in determining the atmospheric composition, particularly of tropospheric ozone, in the northern outer tropical central Pacific. It may lead to more ozone of stratospheric origin in the LT and even in the marine boundary, which may act as harmful pollutants and affect the radiative processes by changing the global budgets of atmospheric hydroxyl radicals.

Keywords: PV intrusion, westerly duct, ozone, Central Pacific

Procedia PDF Downloads 213
131 Teachers' and Learners' Experiences of Learners' Writing in English First Additional Language

Authors: Jane-Francis A. Abongdia, Thandiswa Mpiti

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There is an international concern to develop children’s literacy skills. In many parts of the world, the need to become fluent in a second language is essential for gaining meaningful access to education, the labour market and broader social functioning. In spite of these efforts, the problem still continues. The level of English language proficiency is far from satisfactory and these goals are unattainable by others. The issue is more complex in South Africa as learners are immersed in a second language (L2) curriculum. South Africa is a prime example of a country facing the dilemma of how to effectively equip a majority of its population with English as a second language or first additional language (FAL). Given the multilingual nature of South Africa with eleven official languages, and the position and power of English, the study investigates teachers’ and learners’ experiences on isiXhosa and Afrikaans background learners’ writing in English First Additional Language (EFAL). Moreover, possible causes of writing difficulties and teacher’s practices for writing are explored. The theoretical and conceptual framework for the study is provided by studies on constructivist theories and sociocultural theories. In exploring these issues, a qualitative approach through semi-structured interviews, classroom observations, and document analysis were adopted. This data is analysed by critical discourse analysis (CDA). The study identified a weak correlation between teachers’ beliefs and their actual teaching practices. Although the teachers believe that writing is as important as listening, speaking, reading, grammar and vocabulary, and that it needs regular practice, the data reveal that they fail to put their beliefs into practice. Moreover, the data revealed that learners were disturbed by their home language because when they do not know a word they would write either the isiXhosa or the Afrikaans equivalent. Code-switching seems to have instilled a sense of “dependence on translations” where some learners would not even try to answer English questions but would wait for the teacher to translate the questions into isiXhosa or Afrikaans before they could attempt to give answers. The findings of the study show a marked improvement in the writing performance of learners who used the process approach in writing. These findings demonstrate the need for assisting teachers to shift away from focusing only on learners’ performance (testing and grading) towards a stronger emphasis on the process of writing. The study concludes that the process approach to writing could enable teachers to focus on the various parts of the writing process which can give more freedom to learners to experiment their language proficiency. It would require that teachers develop a deeper understanding of the process/genre approaches to teaching writing advocated by CAPS. All in all, the study shows that both learners and teachers face numerous challenges relating to writing. This means that more work still needs to be done in this area. The present study argues that teachers teaching EFAL learners should approach writing as a critical and core aspect of learners’ education. Learners should be exposed to intensive writing activities throughout their school years.

Keywords: constructivism, English second language, language of learning and teaching, writing

Procedia PDF Downloads 193
130 Assessment of the Impact of Regular Pilates Exercises on Static Balance in Healthy Adult Women: Preliminary Report

Authors: Anna Słupik, Krzysztof Jaworski, Anna Mosiołek, Dariusz Białoszewski

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Background: Maintaining the correct body balance is essential in the prevention of falls in the elderly, which is especially important for women because of postmenopausal osteoporosis and the serious consequences of falls. One of the exercise methods which is very popular among adults, and which may affect body balance in a positive way is the pilates method. The aim of the study was to evaluate the effect of regular pilates exercises on the ability to maintain body balance in static conditions in adult healthy women. Material and methods: The study group consisted of 20 healthy women attending pilates twice a week for at least 1 year. The control group consisted of 20 healthy women physically inactive. Women in the age range from 35 to 50 years old without pain in musculoskeletal system or other pain were only qualified to the groups. Body balance was assessed using MatScan VersaTek platform with Sway Analysis Module based on Matscan Clinical 6.7 software. The balance was evaluated under the following conditions: standing on both feet with eyes open, standing on both feet with eyes closed, one-leg standing (separately on the right and left foot) with eyes open. Each test lasted 30 seconds. The following parameters were calculated: estimated size of the ellipse of 95% confidence, the distance covered by the Center of Gravity (COG), the size of the maximum shift in the sagittal and frontal planes and load distribution between the left and right foot, as well as between rear- and forefoot. Results: It was found that there is significant difference between the groups in favor of the study group in the size of the confidence ellipse and maximum shifts of COG in the sagittal plane during standing on both feet, both with the eyes open and closed (p < 0.05). While standing on one leg both on the right and left leg, with eyes opened there was a significant difference in favor of the study group, in terms of the size of confidence ellipse, the size of the maximum shifts in the sagittal and in the frontal plane (p < 0.05). There were no differences between the distribution of load between the right and left foot (standing with both feet), nor between fore- and rear foot (in standing with both feet or one-leg). Conclusions: 1. Static balance in women exercising regularly by pilates method is better than in inactive women, which may in the future prevent falls and their consequences. 2. The observed differences in maintaining balance in frontal plane in one-leg standing may indicate a positive impact of pilates exercises on the ability to maintain global balance in terms of the reduced support surface. 3. Pilates method can be used as a form preventive therapy for all people who are expected to have problems with body balance in the future, for example in chronic neurological disorders or vestibular problems. 4. The results have shown that further prospective randomized research on a larger and more representative group is needed.

Keywords: balance exercises, body balance, pilates, pressure distribution, women

Procedia PDF Downloads 290
129 Ammonia Bunkering Spill Scenarios: Modelling Plume’s Behaviour and Potential to Trigger Harmful Algal Blooms in the Singapore Straits

Authors: Bryan Low

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In the coming decades, the global maritime industry will face a most formidable environmental challenge -achieving net zero carbon emissions by 2050. To meet this target, the Maritime Port Authority of Singapore (MPA) has worked to establish green shipping and digital corridors with ports of several other countries around the world where ships will use low-carbon alternative fuels such as ammonia for power generation. While this paradigm shift to the bunkering of greener fuels is encouraging, fuels like ammonia will also introduce a new and unique type of environmental risk in the unlikely scenario of a spill. While numerous modelling studies have been conducted for oil spills and their associated environmental impact on coastal and marine ecosystems, ammonia spills are comparatively less well understood. For example, there is a knowledge gap regarding how the complex hydrodynamic conditions of the Singapore Straits may influence the dispersion of a hypothetical ammonia plume, which has different physical and chemical properties compared to an oil slick. Chemically, ammonia can be absorbed by phytoplankton, thus altering the balance of the marine nitrogen cycle. Biologically, ammonia generally serves the role of a nutrient in coastal ecosystems at lower concentrations. However, at higher concentrations, it has been found to be toxic to many local species. It may also have the potential to trigger eutrophication and harmful algal blooms (HABs) in coastal waters, depending on local hydrodynamic conditions. Thus, the key objective of this research paper is to support the development of a model-based forecasting system that can predict ammonia plume behaviour in coastal waters, given prevailing hydrodynamic conditions and their environmental impact. This will be essential as ammonia bunkering becomes more commonplace in Singapore’s ports and around the world. Specifically, this system must be able to assess the HAB-triggering potential of an ammonia plume, as well as its lethal and sub-lethal toxic effects on local species. This will allow the relevant authorities to better plan risk mitigation measures or choose a time window with the ideal hydrodynamic conditions to conduct ammonia bunkering operations with minimal risk. In this paper, we present the first part of such a forecasting system: a jointly coupled hydrodynamic-water quality model that can capture how advection-diffusion processes driven by ocean currents influence plume behaviour and how the plume interacts with the marine nitrogen cycle. The model is then applied to various ammonia spill scenarios where the results are discussed in the context of current ammonia toxicity guidelines, impact on local ecosystems, and mitigation measures for future bunkering operations conducted in the Singapore Straits.

Keywords: ammonia bunkering, forecasting, harmful algal blooms, hydrodynamics, marine nitrogen cycle, oceanography, water quality modeling

Procedia PDF Downloads 46
128 Graphene Metamaterials Supported Tunable Terahertz Fano Resonance

Authors: Xiaoyong He

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The manipulation of THz waves is still a challenging task due to lack of natural materials interacted with it strongly. Designed by tailoring the characters of unit cells (meta-molecules), the advance of metamaterials (MMs) may solve this problem. However, because of Ohmic and radiation losses, the performance of MMs devices is subjected to the dissipation and low quality factor (Q-factor). This dilemma may be circumvented by Fano resonance, which arises from the destructive interference between a bright continuum mode and dark discrete mode (or a narrow resonance). Different from symmetric Lorentz spectral curve, Fano resonance indicates a distinct asymmetric line-shape, ultrahigh quality factor, steep variations in spectrum curves. Fano resonance is usually realized through symmetry breaking. However, if concentric double rings (DR) are placed closely to each other, the near-field coupling between them gives rise to two hybridized modes (bright and narrowband dark modes) because of the local asymmetry, resulting into the characteristic Fano line shape. Furthermore, from the practical viewpoint, it is highly desirable requirement that to achieve the modulation of Fano spectral curves conveniently, which is an important and interesting research topics. For current Fano systems, the tunable spectral curves can be realized by adjusting the geometrical structural parameters or magnetic fields biased the ferrite-based structure. But due to limited dispersion properties of active materials, it is still a tough work to tailor Fano resonance conveniently with the fixed structural parameters. With the favorable properties of extreme confinement and high tunability, graphene is a strong candidate to achieve this goal. The DR-structure possesses the excitation of so-called “trapped modes,” with the merits of simple structure and high quality of resonances in thin structures. By depositing graphene circular DR on the SiO2/Si/ polymer substrate, the tunable Fano resonance has been theoretically investigated in the terahertz regime, including the effects of graphene Fermi level, structural parameters and operation frequency. The results manifest that the obvious Fano peak can be efficiently modulated because of the strong coupling between incident waves and graphene ribbons. As Fermi level increases, the peak amplitude of Fano curve increases, and the resonant peak position shifts to high frequency. The amplitude modulation depth of Fano curves is about 30% if Fermi level changes in the scope of 0.1-1.0 eV. The optimum gap distance between DR is about 8-12 μm, where the value of figure of merit shows a peak. As the graphene ribbon width increases, the Fano spectral curves become broad, and the resonant peak denotes blue shift. The results are very helpful to develop novel graphene plasmonic devices, e.g. sensors and modulators.

Keywords: graphene, metamaterials, terahertz, tunable

Procedia PDF Downloads 324
127 The Rise and Effects of Social Movement on Ethnic Relations in Malaysia: The Bersih Movement as a Case Study

Authors: Nur Rafeeda Daut

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The significance of this paper is to provide an insight on the role of social movement in building stronger ethnic relations in Malaysia. In particular, it focuses on how the BERSIH movement have been able to bring together the different ethnic groups in Malaysia to resist the present political administration that is seen to manipulate the electoral process and oppress the basic freedom of expression of Malaysians. Attention is given on how and why this group emerged and its mobilisation strategies. Malaysia which is a multi-ethnic and multi-religious society gained its independence from the British in 1957. Like many other new nations, it faces the challenges of nation building and governance. From economic issues to racial and religious tension, Malaysia is experiencing high level of corruption and income disparity among the different ethnic groups. The political parties in Malaysia are also divided along ethnic lines. BERSIH which is translated as ‘clean’ is a movement which seeks to reform the current electoral system in Malaysia to ensure equality, justice, free and fair elections. It was originally formed in 2007 as a joint committee that comprised leaders from political parties, civil society groups and NGOs. In April 2010, the coalition developed as an entirely civil society movement unaffiliated to any political party. BERSIH claimed that the electoral roll in Malaysia has been marred by fraud and other irregularities. In 2015, the BERSIH movement organised its biggest rally in Malaysia which also includes 38 other rallies held internationally. Supporters of BERSIH that participated in the demonstration were comprised of all the different ethnic groups in Malaysia. In this paper, two social movement theories are used: resource mobilization theory and political opportunity structure to explain the emergence and mobilization of the BERSIH movement in Malaysia. Based on these two theories, corruption which is believed to have contributed to the income disparity among Malaysians has generated the development of this movement. The rise of re-islamisation values propagated by certain groups in Malaysia and the shift in political leadership has also created political opportunities for this movement to emerge. In line with the political opportunity structure theory, the BERSIH movement will continue to create more opportunities for the empowerment of civil society and the unity of ethnic relations in Malaysia. Comparison is made on the degree of ethnic unity in the country before and after BERSIH was formed. This would include analysing the level of re-islamisation values and also the level of corruption in relation to economic income under the premiership of the former Prime Minister Mahathir and the present Prime Minister Najib Razak. The country has never seen such uprisings like BERSIH where ethnic groups which over the years have been divided by ethnic based political parties and economic disparity joined together with a common goal for equality and fair elections. As such, the BERSIH movement is a unique case where it illustrates the change of political landscape, ethnic relations and civil society in Malaysia.

Keywords: ethnic relations, Malaysia, political opportunity structure, resource mobilization theory and social movement

Procedia PDF Downloads 318
126 Identifying Confirmed Resemblances in Problem-Solving Engineering, Both in the Past and Present

Authors: Colin Schmidt, Adrien Lecossier, Pascal Crubleau, Simon Richir

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Introduction:The widespread availability of artificial intelligence, exemplified by Generative Pre-trained Transformers (GPT) relying on large language models (LLM), has caused a seismic shift in the realm of knowledge. Everyone now has the capacity to swiftly learn how these models can either serve them well or not. Today, conversational AI like ChatGPT is grounded in neural transformer models, a significant advance in natural language processing facilitated by the emergence of renowned LLMs constructed using neural transformer architecture. Inventiveness of an LLM : OpenAI's GPT-3 stands as a premier LLM, capable of handling a broad spectrum of natural language processing tasks without requiring fine-tuning, reliably producing text that reads as if authored by humans. However, even with an understanding of how LLMs respond to questions asked, there may be lurking behind OpenAI’s seemingly endless responses an inventive model yet to be uncovered. There may be some unforeseen reasoning emerging from the interconnection of neural networks here. Just as a Soviet researcher in the 1940s questioned the existence of Common factors in inventions, enabling an Under standing of how and according to what principles humans create them, it is equally legitimate today to explore whether solutions provided by LLMs to complex problems also share common denominators. Theory of Inventive Problem Solving (TRIZ) : We will revisit some fundamentals of TRIZ and how Genrich ALTSHULLER was inspired by the idea that inventions and innovations are essential means to solve societal problems. It's crucial to note that traditional problem-solving methods often fall short in discovering innovative solutions. The design team is frequently hampered by psychological barriers stemming from confinement within a highly specialized knowledge domain that is difficult to question. We presume ChatGPT Utilizes TRIZ 40. Hence, the objective of this research is to decipher the inventive model of LLMs, particularly that of ChatGPT, through a comparative study. This will enhance the efficiency of sustainable innovation processes and shed light on how the construction of a solution to a complex problem was devised. Description of the Experimental Protocol : To confirm or reject our main hypothesis that is to determine whether ChatGPT uses TRIZ, we will follow a stringent protocol that we will detail, drawing on insights from a panel of two TRIZ experts. Conclusion and Future Directions : In this endeavor, we sought to comprehend how an LLM like GPT addresses complex challenges. Our goal was to analyze the inventive model of responses provided by an LLM, specifically ChatGPT, by comparing it to an existing standard model: TRIZ 40. Of course, problem solving is our main focus in our endeavours.

Keywords: artificial intelligence, Triz, ChatGPT, inventiveness, problem-solving

Procedia PDF Downloads 38
125 Strategies for Conserving Ecosystem Functions of the Aravalli Range to Combat Land Degradation: Case of Kishangarh and Tijara Tehsil in Rajasthan, India

Authors: Saloni Khandelwal

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The Aravalli hills are one of the oldest and most distinctive mountain chains of peninsular India spanning in around 692 Km. More than 60% of it falls in the state of Rajasthan and influences ecological equilibrium in about 30% of the state. Because of natural and human-induced activities, physical gaps in the Aravallis are increasing, new gaps are coming up, and its physical structure is changing. There are no strict regulations to protect and monitor the Aravallis and no comprehensive research and study has been done for the enhancement of ecosystem functions of these ranges. Through this study, various factors leading to Aravalli’s degradation are identified and its impacts on selected areas are analyzed. A literature study is done to identify factors responsible for the degradation. To understand the severity of the problem at the lowest level, two tehsils from different districts in Rajasthan, which are the most affected due to illegal mining and increasing physical gaps are selected for the study. Case-1 of three-gram panchayats in Kishangarh Tehsil of Ajmer district focuses on the expanding physical gaps in the Aravalli range, and case-2 of three-gram panchayats in Tijara Tehsil of Alwar district focuses on increasing illegal mining in the Aravalli range. For measuring the degradation, physical, biological and social indicators are identified through literature review and for both the cases analysis is done on the basis of these indicators. Primary survey and focus group discussions are done with villagers, mining owners, illegal miners, and various government officials to understand dependency of people on the Aravalli and its importance to them along with the impact of degradation on their livelihood and environment. From the analysis, it has been found that green cover is continuously decreasing in both cases, dense forest areas do not exist now, the groundwater table is depleting at a very fast rate, soil is losing its moisture resulting in low yield and shift in agriculture. Wild animals which were easily seen earlier are now extinct. Cattles of villagers are dependent on the forest area in the Aravalli range for food, but with a decrease in fodder, their cattle numbers are decreasing. There is a decrease in agricultural land and an increase in scrub and salt-affected land. Analysis of various national and state programmes, acts which were passed to conserve biodiversity has been done showing that none of them is helping much to protect the Aravalli. For conserving the Aravalli and its forest areas, regional level and local level initiatives are required and are proposed in this study. This study is an attempt to formulate conservation and management strategies for the Aravalli range. These strategies will help in improving biodiversity which can lead to the revival of its ecosystem functions. It will also help in curbing the pollution at the regional and local level. All this will lead to the sustainable development of the region.

Keywords: Aravalli, ecosystem, LULC, Rajasthan

Procedia PDF Downloads 110
124 Theoretical Study on the Visible-Light-Induced Radical Coupling Reactions Mediated by Charge Transfer Complex

Authors: Lishuang Ma

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Charge transfer (CT) complex, also known as Electron donor-acceptor (EDA) complex, has received attentions increasingly in the field of synthetic chemistry community, due to the CT complex can absorb the visible light through the intermolecular charge transfer excited states, various of catalyst-free photochemical transformations under mild visible-light conditions. However, a number of fundamental questions are still ambiguous, such as the origin of visible light absorption, the photochemical and photophysical properties of the CT complex, as well as the detailed mechanism of the radical coupling pathways mediated by CT complex. Since these are critical factors for target-specific design and synthesis of more new-type CT complexes. To this end, theoretical investigations were performed in our group to answer these questions based on multiconfigurational perturbation theory. The photo-induced fluoroalkylation reactions are mediated by CT complexes, which are formed by the association of an acceptor of perfluoroalkyl halides RF−X (X = Br, I) and a suitable donor molecule such as β-naphtholate anion, were chosen as a paradigm example in this work. First, spectrum simulations were carried out by both CASPT2//CASSCF/PCM and TD-DFT/PCM methods. The computational results showed that the broadening spectra in visible light range (360-550nm) of the CT complexes originate from the 1(σπ*) excitation, accompanied by an intermolecular electron transfer, which was also found closely related to the aggregate states of the donor and acceptor. Moreover, from charge translocation analysis, the CT complex that showed larger charge transfer in the round state would exhibit smaller charge transfer in excited stated of 1(σπ*), causing blue shift relatively. Then, the excited-state potential energy surface (PES) was calculated at CASPT2//CASSCF(12,10)/ PCM level of theory to explore the photophysical properties of the CT complexes. The photo-induced C-X (X=I, Br) bond cleavage was found to occur in the triplet state, which is accessible through a fast intersystem crossing (ISC) process that is controlled by the strong spin-orbit coupling resulting from the heavy iodine and bromine atoms. Importantly, this rapid fragmentation process can compete and suppress the backward electron transfer (BET) event, facilitating the subsequent effective photochemical transformations. Finally, the reaction pathways of the radical coupling were also inspected, which showed that the radical chain propagation pathway could easy to accomplish with a small energy barrier no more than 3.0 kcal/mol, which is the key factor that promote the efficiency of the photochemical reactions induced by CT complexes. In conclusion, theoretical investigations were performed to explore the photophysical and photochemical properties of the CT complexes, as well as the mechanism of radical coupling reactions mediated by CT complex. The computational results and findings in this work can provide some critical insights into mechanism-based design for more new-type EDA complexes

Keywords: charge transfer complex, electron transfer, multiconfigurational perturbation theory, radical coupling

Procedia PDF Downloads 117
123 Iraqi Women’s Rights Under State Civil Law and Conservative Influences: A Study of Legal Documents and Social Implementation

Authors: Rose Hattab

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Women have been an important dynamic in religious context and the state-building process of Arab countries throughout history. During the 1970s as the movement for women’s activism and rights developed, the Iraqi state under the Ba’ath Party began to provide Iraqi women with legal and civil rights. This was done to liberate women from the grasps of social traditions and was a tangible espousing of equality between men and women in the process of nation-building. Whereas women’s rights were stronger and more supported throughout the earliest years of the Ba’ath Regime (1970-1990), the aftermath of the Gulf War and economic sanctions on the conditions of Iraqi society laid the foundation for a division of women’s rights between civil and religious authorities. Personal status codes that were secured in 1959 were being pushed back by amendments made in coordination with religious leaders. Civil laws were present on paper, but religious authority took prominence in practice. The written legal codes were inclusive of women’s rights, but there is not an active or ensured practice of these rights within Iraqi society. This is due to many different factors, such as religious, sectarian, political and conservative reasons that hold back or limit the ability for Iraqi women to have autonomy in aspects such as participation in the workforce, getting married, and ensuring social justice. This paper argues that the Personal Status Code introduced in 1959 – which replaced Sharia-run courts with personal status courts – provided Iraqi women with equality and increased mobility in social and economic dynamics. The statewide crisis felt after the Gulf War and the economic sanctions imposed by the United Nations led to a stark shift in the Ba’ath party’s political ideology. This ideological turn guided the social system to the embracement of social conservatism and religious traditions in the 1990s. The effect of this implementation continued after the establishment of a new Iraqi government during 2003-2005. Consequently, Iraqi women's rights in employment, marriage, and family became divided into paper and practice by religious authorities and civil law from that period to the present day. This paper also contributes to the literature by expanding on the gap between legal codes on paper and in practice, through providing an analysis of Iraqi women’s rights in the Iraqi Constitution of 2005 and Iraq’s Penal Code. The turn to conservative and religious traditions is derived from the multiplicity of identities that make up the Iraqi social fabric. In the aftermath of a totalitarian regime, active wars, and economic sanctions, the Iraqi people attempted to unite together through their different identities to create a sense of security in the midst of violence and chaos. This is not an excuse to diminish the importance of women’s rights, but in the process of building a new nation-state, women were lost from the narrative. Thus, the presence of gender equity is found in the written text but is not practiced and upheld in the social context.

Keywords: civil rights, Iraqi women, nation building, religion and conflict

Procedia PDF Downloads 122
122 Thermal Stress and Computational Fluid Dynamics Analysis of Coatings for High-Temperature Corrosion

Authors: Ali Kadir, O. Anwar Beg

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Thermal barrier coatings are among the most popular methods for providing corrosion protection in high temperature applications including aircraft engine systems, external spacecraft structures, rocket chambers etc. Many different materials are available for such coatings, of which ceramics generally perform the best. Motivated by these applications, the current investigation presents detailed finite element simulations of coating stress analysis for a 3- dimensional, 3-layered model of a test sample representing a typical gas turbine component scenario. Structural steel is selected for the main inner layer, Titanium (Ti) alloy for the middle layer and Silicon Carbide (SiC) for the outermost layer. The model dimensions are 20 mm (width), 10 mm (height) and three 1mm deep layers. ANSYS software is employed to conduct three types of analysis- static structural, thermal stress analysis and also computational fluid dynamic erosion/corrosion analysis (via ANSYS FLUENT). The specified geometry which corresponds to corrosion test samples exactly is discretized using a body-sizing meshing approach, comprising mainly of tetrahedron cells. Refinements were concentrated at the connection points between the layers to shift the focus towards the static effects dissipated between them. A detailed grid independence study is conducted to confirm the accuracy of the selected mesh densities. To recreate gas turbine scenarios; in the stress analysis simulations, static loading and thermal environment conditions of up to 1000 N and 1000 degrees Kelvin are imposed. The default solver was used to set the controls for the simulation with the fixed support being set as one side of the model while subjecting the opposite side to a tabular force of 500 and 1000 Newtons. Equivalent elastic strain, total deformation, equivalent stress and strain energy were computed for all cases. Each analysis was duplicated twice to remove one of the layers each time, to allow testing of the static and thermal effects with each of the coatings. ANSYS FLUENT simulation was conducted to study the effect of corrosion on the model under similar thermal conditions. The momentum and energy equations were solved and the viscous heating option was applied to represent improved thermal physics of heat transfer between the layers of the structures. A Discrete Phase Model (DPM) in ANSYS FLUENT was employed which allows for the injection of continuous uniform air particles onto the model, thereby enabling an option for calculating the corrosion factor caused by hot air injection (particles prescribed 5 m/s velocity and 1273.15 K). Extensive visualization of results is provided. The simulations reveal interesting features associated with coating response to realistic gas turbine loading conditions including significantly different stress concentrations with different coatings.

Keywords: thermal coating, corrosion, ANSYS FEA, CFD

Procedia PDF Downloads 119
121 An Exploratory Study of the Ghanaian Music Industry: Its Impacts on the Economy and Society

Authors: Ralph Nyadu-Addo, Francis Matambalya, Utz Dornberger

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The global music industry is a multi-billion dollar sector. The potential of Africa’s music industry is widely recognised in the socio-economic development milieu. It has impacted positively on several sectors including most especially the tourism, media and information, communication technology (ICT) among others. It is becoming increasingly clear that even in Africa (as demonstrated in Nigeria) that in addition to its intrinsic value, the sector has significant economic returns. UNCTAD observed, the creative industries offer some of the best prospects for high growth in least developed countries. The statistics from Africa may be far lower than similar sectors in developed countries but it goes to give further credence to several UNCTAD publications which say the creative industry is under researched and its potential under-estimated but holds the key to its rapid development The emerging creative economy (music in particular) has become a leading component of economic growth, employment, trade, innovation, and social cohesion in many countries. In line with these developments, the Ghana government recognizes the potential that the Creative Industries have to shape and reinforce Ghana’s economic growth. Creative sectors, particularly music, tend to rely less on sophisticated infrastructure or capital-intensive investment. Potential is particularly abundant in Africa, where musical creativity is rich, diverse, well-loved, and constantly evolving while drawing on strong traditions. The development of a popular music industry thus represents low-hanging fruit for most African economies says the World Bank. As we shift towards economic diversification using the creative industry, value is increasingly created at the intersection of arts, business and technology. Cultural and creative entrepreneurs are leading this trend. It is one of the areas where value is captured within the country as emerging trends have shown in Nigeria and Ghana among others. Yet, evidence shows that the potential of the cultural and creative sectors remains largely untapped. Furthermore, its socio-economic impact remains under-researched in many developing countries and its dynamics unknown. Despite its huge influence on music repertoire across the globe, most countries in Africa have not historically been significant markets for the international music industry. Today, that is beginning to change. Generally, reliable and adequate literature about music in the sub-region is difficult to obtain. The growing interests in academia and business cycles about a reliable data on the growing music industry in developing countries have called for an urgent need to undertake this research. Research questions: i. Who are the major stakeholders in the music value chain in Ghana? ii. How much of value is captured domestically iii. What is the economic impact of the Ghanaian music industry iv. How has the advent of ICT (internet) impacted on the music landscape? Research sources will be mainly through interviews of major stakeholders, baseline study of the industry by KPMG and content analysis of related newspapers and magazines.

Keywords: economic impact, information communications technology (ICT), music-industry, value chain

Procedia PDF Downloads 275
120 Comparative Review Of Models For Forecasting Permanent Deformation In Unbound Granular Materials

Authors: Shamsulhaq Amin

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Unbound granular materials (UGMs) are pivotal in ensuring long-term quality, especially in the layers under the surface of flexible pavements and other constructions. This study seeks to better understand the behavior of the UGMs by looking at popular models for predicting lasting deformation under various levels of stresses and load cycles. These models focus on variables such as the number of load cycles, stress levels, and features specific to materials and were evaluated on the basis of their ability to accurately predict outcomes. The study showed that these factors play a crucial role in how well the models work. Therefore, the research highlights the need to look at a wide range of stress situations to more accurately predict how much the UGMs bend or shift. The research looked at important factors, like how permanent deformation relates to the number of times a load is applied, how quickly this phenomenon happens, and the shakedown effect, in two different types of UGMs: granite and limestone. A detailed study was done over 100,000 load cycles, which provided deep insights into how these materials behave. In this study, a number of factors, such as the level of stress applied, the number of load cycles, the density of the material, and the moisture present were seen as the main factors affecting permanent deformation. It is vital to fully understand these elements for better designing pavements that last long and handle wear and tear. A series of laboratory tests were performed to evaluate the mechanical properties of materials and acquire model parameters. The testing included gradation tests, CBR tests, and Repeated load triaxial tests. The repeated load triaxial tests were crucial for studying the significant components that affect deformation. This test involved applying various stress levels to estimate model parameters. In addition, certain model parameters were established by regression analysis, and optimization was conducted to improve outcomes. Afterward, the material parameters that were acquired were used to construct graphs for each model. The graphs were subsequently compared to the outcomes obtained from the repeated load triaxial testing. Additionally, the models were evaluated to determine if they demonstrated the two inherent deformation behaviors of materials when subjected to repetitive load: the initial phase, post-compaction, and the second phase volumetric changes. In this study, using log-log graphs was key to making the complex data easier to understand. This method made the analysis clearer and helped make the findings easier to interpret, adding both precision and depth to the research. This research provides important insight into picking the right models for predicting how these materials will act under expected stress and load conditions. Moreover, it offers crucial information regarding the effect of load cycle and permanent deformation as well as the shakedown effect on granite and limestone UGMs.

Keywords: permanent deformation, unbound granular materials, load cycles, stress level

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119 Negotiating Communication Options for Deaf-Disabled Children

Authors: Steven J. Singer, Julianna F. Kamenakis, Allison R. Shapiro, Kimberly M. Cacciato

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Communication and language are topics frequently studied among deaf children. However, there is limited research that focuses specifically on the communication and language experiences of Deaf-Disabled children. In this ethnography, researchers investigated the language experiences of six sets of parents with Deaf-Disabled children who chose American Sign Language (ASL) as the preferred mode of communication for their child. Specifically, the researchers were interested in the factors that influenced the parents’ decisions regarding their child’s communication options, educational placements, and social experiences. Data collection in this research included 18 hours of semi-structured interviews, 20 hours of participant observations, over 150 pages of reflexive journals and field notes, and a 2-hour focus group. The team conducted constant comparison qualitative analysis using NVivo software and an inductive coding procedure. The four researchers each read the data several times until they were able to chunk it into broad categories about communication and social influences. The team compared the various categories they developed, selecting ones that were consistent among researchers and redefining categories that differed. Continuing to use open inductive coding, the research team refined the categories until they were able to develop distinct themes. Two team members developed each theme through a process of independent coding, comparison, discussion, and resolution. The research team developed three themes: 1) early medical needs provided time for the parents to explore various communication options for their Deaf-Disabled child, 2) without intervention from medical professionals or educators, ASL emerged as a prioritized mode of communication for the family, 3) atypical gender roles affected familial communication dynamics. While managing the significant health issues of their Deaf-Disabled child at birth, families and medical professionals were so fixated on tending to the medical needs of the child that the typical pressures of determining a mode of communication were deprioritized. This allowed the families to meticulously research various methods of communication, resulting in an informed, rational, and well-considered decision to use ASL as the primary mode of communication with their Deaf-Disabled child. It was evident that having a Deaf-Disabled child meant an increased amount of labor and responsibilities for parents. This led to a shift in the roles of the family members. During the child’s development, the mother transformed from fulfilling the stereotypical roles of nurturer and administrator to that of administrator and champion. The mother facilitated medical proceedings and educational arrangements while the father became the caretaker and nurturer of their Deaf-Disabled child in addition to the traditional role of earning the family’s primary income. Ultimately, this research led to a deeper understanding of the critical role that time plays in parents’ decision-making process regarding communication methods with their Deaf-Disabled child.

Keywords: American Sign Language, deaf-disabled, ethnography, sociolinguistics

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118 Graphene Supported Nano Cerium Oxides Hybrid as an Electrocatalyst for Oxygen Reduction Reactions

Authors: Siba Soren, Purnendu Parhi

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Today, the world is facing a severe challenge due to depletion of traditional fossil fuels. Scientists across the globe are working for a solution that involves a dramatic shift to practical and environmentally sustainable energy sources. High-capacity energy systems, such as metal-air batteries, fuel cells, are highly desirable to meet the urgent requirement of sustainable energies. Among the fuel cells, Direct methanol fuel cells (DMFCs) are recognized as an ideal power source for mobile applications and have received considerable attention in recent past. In this advanced electrochemical energy conversion technologies, Oxygen Reduction Reaction (ORR) is of utmost importance. However, the poor kinetics of cathodic ORR in DMFCs significantly hampers their possibilities of commercialization. The oxygen is reduced in alkaline medium either through a 4-electron (equation i) or a 2-electron (equation ii) reduction pathway at the cathode ((i) O₂ + 2H₂O + 4e⁻ → 4OH⁻, (ii) O₂ + H₂O + 2e⁻ → OH⁻ + HO₂⁻ ). Due to sluggish ORR kinetics the ability to control the reduction of molecular oxygen electrocatalytically is still limited. The electrocatalytic ORR starts with adsorption of O₂ on the electrode surface followed by O–O bond activation/cleavage and oxide removal. The reaction further involves transfer of 4 electrons and 4 protons. The sluggish kinetics of ORR, on the one hand, demands high loading of precious metal-containing catalysts (e.g., Pt), which unfavorably increases the cost of these electrochemical energy conversion devices. Therefore, synthesis of active electrocatalyst with an increase in ORR performance is need of the hour. In the recent literature, there are many reports on transition metal oxide (TMO) based ORR catalysts for their high activity TMOs are also having drawbacks like low electrical conductivity, which seriously affects the electron transfer process during ORR. It was found that 2D graphene layer is having high electrical conductivity, large surface area, and excellent chemical stability, appeared to be an ultimate choice as support material to enhance the catalytic performance of bare metal oxide. g-C₃N₄ is also another candidate that has been used by the researcher for improving the ORR performance of metal oxides. This material provides more active reaction sites than other N containing carbon materials. Rare earth oxide like CeO₂ is also a good candidate for studying the ORR activity as the metal oxide not only possess unique electronic properties but also possess catalytically active sites. Here we will discuss the ORR performance (in alkaline medium) of N-rGO/C₃N₄ supported nano Cerium Oxides hybrid synthesized by microwave assisted Solvothermal method. These materials exhibit superior electrochemical stability and methanol tolerance capability to that of commercial Pt/C.

Keywords: oxygen reduction reaction, electrocatalyst, cerium oxide, graphene

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117 State and Benefit: Delivering the First State of the Bays Report for Victoria

Authors: Scott Rawlings

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Victoria’s first State of the Bays report is an historic baseline study of the health of Port Phillip Bay and Western Port. The report includes 50 assessments of 36 indicators across a broad array of topics from the nitrogen cycle and water quality to key marine species and habitats. This paper discusses the processes for determining and assessing the indicators and comments on future priorities identified to maintain and improve the health of these water ways. Victoria’s population is now at six million, and growing at a rate of over 100,000 people per year - the highest increase in Australia – and the population of greater Melbourne is over four million. Port Phillip Bay and Western Port are vital marine assets at the centre of this growth and will require adaptive strategies if they are to remain in good condition and continue to deliver environmental, economic and social benefits. In 2014, it was in recognition of these pressures that the incoming Victorian Government committed to reporting on the state of the bays every five years. The inaugural State of the Bays report was issued by the independent Victorian Commissioner for Environmental Sustainability. The report brought together what is known about both bays, based on existing research. It was a baseline on which future reports will build and, over time, include more of Victoria’s marine environment. Port Phillip Bay and Western Port generally demonstrate healthy systems. Specific threats linked to population growth are a significant pressure. Impacts are more significant where human activity is more intense and where nutrients are transported to the bays around the mouths of creeks and drainage systems. The transport of high loads of nutrients and pollutants to the bays from peak rainfall events is likely to increase with climate change – as will sea level rise. Marine pests are also a threat. More than 100 introduced marine species have become established in Port Phillip Bay and can compete with native species, alter habitat, reduce important fish stocks and potentially disrupt nitrogen cycling processes. This study confirmed that our data collection regime is better within the Marine Protected Areas of Port Phillip Bay than in other parts. The State of the Bays report is a positive and practical example of what can be achieved through collaboration and cooperation between environmental reporters, Government agencies, academic institutions, data custodians, and NGOs. The State of the Bays 2016 provides an important foundation by identifying knowledge gaps and research priorities for future studies and reports on the bays. It builds a strong evidence base to effectively manage the bays and support an adaptive management framework. The Report proposes a set of indicators for future reporting that will support a step-change in our approach to monitoring and managing the bays – a shift from reporting only on what we do know, to reporting on what we need to know.

Keywords: coastal science, marine science, Port Phillip Bay, state of the environment, Western Port

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116 Effect of Ion Irradiation on the Microstructure and Properties of Chromium Coatings on Zircaloy-4 Substrate

Authors: Alexia Wu, Joel Ribis, Jean-Christophe Brachet, Emmanuel Clouet, Benoit Arnal, Elodie Rouesne, Stéphane Urvoy, Justine Roubaud, Yves Serruys, Frederic Lepretre

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To enhance the safety of Light Water Reactor, accident tolerant fuel (ATF) claddings materials are under development. In the framework of CEA-AREVA-EDF collaborative program on ATF cladding materials, CEA has engaged specific studies on chromium coated zirconium alloys. Especially for Loss-of-Coolant-Accident situations, chromium coated claddings have shown some additional 'coping' time before achieving full embrittlement of the oxidized cladding, when compared to uncoated references – both tested in steam environment up to 1300°C. Nevertheless, the behavior of chromium coatings and the stability of the Zr-Cr interface under neutron irradiation remain unknown. Two main points are addressed: 1. Bulk Cr behavior under irradiation: Due to its BCC crystallographic structure, Cr is prone to Ductile-to-Brittle-Transition at quite high temperature. Irradiation could be responsible for a significant additional DBTT shift towards higher temperatures. 2. Zircaloy/Cr interface behavior under irradiation: Preliminary TEM examinations of un-irradiated samples revealed a singular Zircaloy-4/Cr interface with nanometric intermetallic phase layers. Such particular interfaces highlight questions of how they would behave under irradiation - intermetallic zirconium phases are known to be more or less stable under irradiations. Another concern is a potential enhancement of chromium diffusion into the zirconium-alpha based substrate. The purpose of this study is then to determine the behavior of such coatings after ion irradiations, as a surrogate to neutron irradiation. Ion irradiations were performed at the Jannus-Saclay facility (France). 20 MeV Kr8+ ions at 400°C with a flux of 2.8x1011 ions.cm-2.s-1 were used to irradiate chromium coatings of 1-2 µm thick on Zircaloy-4 sheets substrate. At the interface, the calculated damage is close to 10 dpa (SRIM, Quick Calculation Damage mode). Thin foil samples were prepared with FIB for both as-received and irradiated coated samples. Transmission Electron Microscopy (TEM) and in-situ tensile tests in a Scanning Electron Microscope are being used to characterize the un-irradiated and irradiated materials. High Resolution TEM highlights a great complexity of the interface before irradiation since it is formed of an alternation of intermetallic phases – C14 and C15. The interfaces formed by these intermetallic phases with chromium and zirconium show semi-coherency. Chemical analysis performed before irradiation shows some iron enrichment at the interface. The chromium coating bulk microstructures and properties are also studied before and after irradiation. On-going in-situ tensile tests focus on the capacity of chromium coatings to sustain some plastic deformation when tested up to 350°C. The stability of the Cr/Zr interface is shown after ion irradiation up to 10 dpa. This observation constitutes the first result after irradiation on these new coated claddings materials.

Keywords: accident tolerant fuel, HRTEM, interface, ion-irradiation

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115 Partially Aminated Polyacrylamide Hydrogel: A Novel Approach for Temporary Oil and Gas Well Abandonment

Authors: Hamed Movahedi, Nicolas Bovet, Henning Friis Poulsen

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Following the advent of the Industrial Revolution, there has been a significant increase in the extraction and utilization of hydrocarbon and fossil fuel resources. However, a new era has emerged, characterized by a shift towards sustainable practices, namely the reduction of carbon emissions and the promotion of renewable energy generation. Given the substantial number of mature oil and gas wells that have been developed inside the petroleum reservoir domain, it is imperative to establish an environmental strategy and adopt appropriate measures to effectively seal and decommission these wells. In general, the cement plug serves as a material for plugging purposes. Nevertheless, there exist some scenarios in which the durability of such a plug is compromised, leading to the potential escape of hydrocarbons via fissures and fractures within cement plugs. Furthermore, cement is often not considered a practical solution for temporary plugging, particularly in the case of well sites that have the potential for future gas storage or CO2 injection. The Danish oil and gas industry has promising potential as a prospective candidate for future carbon dioxide (CO2) injection, hence contributing to the implementation of carbon capture strategies within Europe. The primary reservoir component consists of chalk, a rock characterized by limited permeability. This work focuses on the development and characterization of a novel hydrogel variant. The hydrogel is designed to be injected via a low-permeability reservoir and afterward undergoes a transformation into a high-viscosity gel. The primary objective of this research is to explore the potential of this hydrogel as a new solution for effectively plugging well flow. Initially, the synthesis of polyacrylamide was carried out using radical polymerization inside the confines of the reaction flask. Subsequently, with the application of the Hoffman rearrangement, the polymer chain undergoes partial amination, facilitating its subsequent reaction with the crosslinker and enabling the formation of a hydrogel in the subsequent stage. The organic crosslinker, glutaraldehyde, was employed in the experiment to facilitate the formation of a gel. This gel formation occurred when the polymeric solution was subjected to heat within a specified range of reservoir temperatures. Additionally, a rheological survey and gel time measurements were conducted on several polymeric solutions to determine the optimal concentration. The findings indicate that the gel duration is contingent upon the starting concentration and exhibits a range of 4 to 20 hours, hence allowing for manipulation to accommodate diverse injection strategies. Moreover, the findings indicate that the gel may be generated in environments characterized by acidity and high salinity. This property ensures the suitability of this substance for application in challenging reservoir conditions. The rheological investigation indicates that the polymeric solution exhibits the characteristics of a Herschel-Bulkley fluid with somewhat elevated yield stress prior to solidification.

Keywords: polyacrylamide, hofmann rearrangement, rheology, gel time

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