Search results for: pitch moment

Authors: Zwelenkani Mdlalose

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From the moment Covid 19 was declared a pandemic it became clear that conspiracy theories would significantly impact our response to the crisis that the virus was to become. Central to the interest in conspiracy theories evoked by a pandemic is a more general concern for the impact they have on society and social harmony. The specific brand of Conspiracy Theory that is in question is not any and all theories about conspiracies but rather those conspiracy theories which contradict official accounts. For example, where the official account on the terrorist attacks of September 11 2001 is of a conspiracy involving 19 militants associated with the Islamic extremist group al-Qaeda against targets in the United States, the nature of conspiracy theory under study is the one contradicting this official account to the extent that its attributes the attacks not to al-Qaeda militants but to actors in the United States government itself. The study is not an investigation into the truth value of conspiracy theories but rather an attempt at observing the essential qualities of the type of belief that is belief in conspiracy theories compared to belief in official accounts provided by authoritative sources such as governments, experts and mainstream media. These qualities include the psychological, epistemic and socio-political foundations on which belief in conspiracy theories are established. Based on a foundational understanding of the sort of belief that are beliefs in conspiracy theories, we may then extrapolate implied ethical demands on both authoritative bodies and actors as well as believers in conspiracy theories. For example: in their unofficial ‘non-factual’ status, is there not some violation of epistemic right in the same way we observe in cases where people are prejudiced because of their religious beliefs? In other words, is there an epistemic injustice suffered by believers in conspiracy theories in the way their beliefs are rejected as illegitimate? Conversely, to what extent do believers bear an epistemic responsibility in their adoption of their beliefs in conspiracy theories. From this position, perhaps we can then develop responses to the problem that foster greater social harmony even in the midst of suspicion and distrust.

Keywords: conspiracy theories, subjugated knowledge, epistemic injustice, epistemic responsibility

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Authors: Chasity O'Connell

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The use of social media and networking sites play a significant role in the lives of adolescents and adults. While research supports that social support and connectedness in general is beneficial; the nature of communication and interaction through social media and its subsequent benefits and impacts could be arguably different. As such, this research aims to explore a specific facet of social media interaction called fear of missing out, or 'FOMO' and investigate its relationship within the context of life stressors, social media usage, anxiety and depressive-symptoms, mindfulness, and psychological well-being. FOMO is the 'uneasy and sometimes all-consuming feeling that you’re missing out—that your peers are doing, in the know about, or in possession of more or something better than you'. Research suggests that FOMO can influence an individual’s level of engagement with friends and social media consumption, drive decisions on participating in various online or offline activities, and ultimately impact mental health. This study hopes to explore the potentially mitigating influence of mindfulness and values-based interventions in reducing the discomfort and distress that can accompany FOMO and increase the sense of psychological well-being in allowing for a more thoughtful and deliberate engagement in life. This study will include an intervention component wherein participants (comprised of university students and adults in the community) will partake in a six-week, group-based intervention focusing on learning practical mindfulness skills and values-exploration exercises (along with a waitlist control group). In doing so, researchers hope to understand if interventions centered on increasing one’s awareness of the present moment and one’s internal values impact decision-making and well-being with regard to social interaction and relationships.

Keywords: FOMO, mindfulness, values, stress, psychological well-being, intervention, distress

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Authors: Vinay Kumar Vanjakula, Frank Adam

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The generation of electricity through wind power is one of the leading renewable energy generation methods. Due to abundant higher wind speeds far away from shore, the construction of offshore wind turbines began in the last decades. However, the installation of offshore foundation-based (monopiles) wind turbines in deep waters are often associated with technical and financial challenges. To overcome such challenges, the concept of floating wind turbines is expanded as the basis of the oil and gas industry. For such a floating system, stabilization in harsh conditions is a challenging task. For that, a robust heavy-weight gravity anchor is needed. Transportation of such anchor requires a heavy vessel that increases the cost. To lower the cost, the gravity anchor is designed with ballast chambers that allow the anchor to float while towing and filled with water when lowering to the planned seabed location. The presence of such a large structure may influence the flow field around it. The changes in the flow field include, formation of vortices, turbulence generation, waves or currents flow breaking and pressure differentials around the seabed sediment. These changes influence the installation process. Also, after installation and under operating conditions, the flow around the anchor may allow the local seabed sediment to be carried off and results in Scour (erosion). These are a threat to the structure's stability. In recent decades, rapid developments of research work and the knowledge of scouring on fixed structures (bridges and monopiles) in rivers and oceans have been carried out, and very limited research work on scouring around a bluff-shaped gravity anchor. The objective of this study involves the application of different numerical models to simulate the anchor towing under waves and calm water conditions. Anchor lowering involves the investigation of anchor movements at certain water depths under wave/current. The motions of anchor drift, heave, and pitch is of special focus. The further study involves anchor scour, where the anchor is installed in the seabed; the flow of underwater current around the anchor induces vortices mainly at the front and corners that develop soil erosion. The study of scouring on a submerged gravity anchor is an interesting research question since the flow not only passes around the anchor but also over the structure that forms different flow vortices. The achieved results and the numerical model will be a basis for the development of other designs and concepts for marine structures. The Computational Fluid Dynamics (CFD) numerical model will build in OpenFOAM and other similar software.

Keywords: anchor lowering, anchor towing, gravity anchor, computational fluid dynamics, scour

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Authors: Zsuzsanna Fejes

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The aim of this paper is to provide an overview of the legal history of constitutionalism in Hungary, in focus of the democratic transitions in 1989-1990, describing the historical and political background of the changes and presenting the main and most important features of the new democracy, and institutional and legal orders. In Hungary the evolved political, economic and moral crisis prior to the constitutional years 2010-11 had been such a constitutional moment, which led to an opportune and unavoidable change at the same time. The Hungarian constitutional power intended to adopt a new constitution, which was competent to create a common constitutional identity and to express a national unity. The Hungarian Parliament on 18th April 2011 passed the New Fundamental Law. The new Fundamental Law rich in national values meant a new challenge for the academics, lawyers, and political scientists. Not only the classical political science, but also the constitutional law and theory have to struggle with the interpretation of the new declarations about national constitutional values in the Fundamental Law. The main features and structure of the new Fundamental Law will be analysed, and given a detailed interpretation of the Preamble as a declaration of constitutional values. During the examination of the Preamble shall be cleared up the components of Hungarian statehood and national unity, individual and common human rights, the practical and theoretical demand on national sovereignty, and the content and possibilities for the interpretation of the achievements of the historical Constitution. These scopes of problems will be presented during the examination of the text of National Avowal, as a preamble of the Fundamental Law. It is examined whether the Fundamental Law itself could be suitable and sufficient means to citizens of Hungary to express the ideas therein as their own, it will be analysed how could the national and European common traditions, values and principles stated in the Fundamental Law mean maintenance in Hungary’s participation in the European integration.

Keywords: common constitutional values, constitutionalism, national identity, national sovereignty, national unity, statehood

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Authors: Jingqian Xiao

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The rapid wave of urbanization triggered by China’s economic growth over the past few decades has inevitably impacted the country’s educational landscape. Educational spaces in China shifted during the 1990s when, due to the government’s tax reforms, large numbers of rural schools were abolished or merged with urban schools, resulting in an “urbanization” of school content and values. While urbanized education is now the status quo, there is as yet no literature review, to our best knowledge, that comprehensively summarizes academic work on this phenomenon. Besides, most research on Chinese educational urbanization relies on basic policy deductions, and there is room for improvement in both the quality and quantity of empirical research on this topic. This paper, therefore, reviews relevant literature on educational urbanization in China from three interrelated factors that shape educational inequality between urban and rural China, namely the urbanization in educational space, school content, and educational values. Results find that the main discussion on Chinese educational urbanization often addresses how Chinese rural education can be improved by reforming the urbanization model to revitalize rural society. While the complete urbanization of Chinese education does not seem feasible, the rapidly changing nature of China’s development patterns and political landscape means the course of Chinese education may shift at any time. When the government does decide to fulfill its intentions to improve the countryside, many formerly dilapidated rural schools may be revived, but for the moment, both rural and urban education in China suffers from governmental neglect. In addition, the breakout of COVID-19, which led to a sudden spread of online education that reopened the gap between the educational conditions and the cultural capital of families in rural and urban areas, has also posed new challenges for China’s attempts to resolve conflicting interests between urban and rural schools and promote educational equality.

Keywords: Chinese education, educational inequality, rural and urban education, urbanization in education

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Authors: Ora Geiger

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Reading is a cognitive process of deciphering visual signs to produce meaning. During the reading process, written information of symbols and signs is received in the person’s eye and processed in the brain. This definition is relevant to both the reading of letters and the reading of musical notation. But while the letters of the alphabet are signs determined arbitrarily, notes are recorded systematically on a staff, with the location of each note on the staff indicating its relative pitch. In this paper, the researcher specifies the characteristics of alphabet reading in comparison to musical notation reading, and discusses the question whether a person diagnosed with dyslexia will necessarily have difficulty in reading musical notes. Dyslexia is a learning disorder that makes it difficult to acquire alphabet-reading skills due to difficulties expressed in the identification of letters, spelling, and other language deciphering skills. In order to read, one must be able to connect a symbol with a sound and to join the sounds into words. A person who has dyslexia finds it difficult to translate a graphic symbol into the sound that it represents. When teaching reading to children diagnosed with dyslexia, the multi-sensory approach, supporting the activation and involvement of most of the senses in the learning process, has been found to be particularly effective. According to this approach, when most senses participate in the reading learning process, it becomes more effective. During years of experience, the researcher, who is a music specialist, has been following the music reading learning process of elementary school age students, some of them diagnosed with Dyslexia, while studying to play soprano (descant) recorder. She argues that learning music reading while studying to play a musical instrument is a multi-sensory experience by its nature. The senses involved are: sight, hearing, touch, and the kinesthetic sense (motion), which provides the brain with information on the relative positions of the body. In this way, the learner experiences simultaneously visual, auditory, tactile, and kinesthetic impressions. The researcher concludes that there should be no contra-indication for teaching standard music reading to children with dyslexia if an appropriate process is offered. This conclusion is based on two main characteristics of music reading: (1) musical notation system is a systematic, logical, relative set of symbols written on a staff; and (2) music reading learning connected with playing a musical instrument is by its nature a multi-sensory activity since it combines sight, hearing, touch, and movement. This paper describes music reading teaching procedures and provides unique teaching methods that have been found to be effective for students who were diagnosed with Dyslexia. It provides theoretical explanations in addition to guidelines for music education practices.

Keywords: alphabet reading, dyslexia, multisensory teaching method, music reading, recorder playing

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Authors: Eli Maria Pazzianotto-Forti, Patrícia Brigatto, Letícia Baltieri, Carolina Moraes Da Costa, Maura Rigoldi Simoes Da Rocha, Irineu Rasera Jr

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The application of positive pressure in airway can contribute to the restoration of lung volumes, capacities and prevent respiratory complications. The aim was to investigate the use of Bilevel Positive Airway Pressure (BIPAP) in morbidly obese in two moments in postoperative bariatric surgery: In the post-anesthetic recovery (PAR) and on the 1st postoperative day (1stPO). Twenty morbidly obese, aged between 25 and 55 years, underwent pulmonary function test and chest X-ray preoperatively and on the day of discharge (2nd day after surgery). They were randomly allocated in groups. GPAR: received BIPAP treatment in PAR, for an hour and G1stPO: received BIPAP for one hour, on the 1stPO. There were significant reductions in slow vital capacity (SVC) (p=0.0007), inspiratory reserve volume (IRV) (p=0.0016) and forced vital capacity (FVC) (p=0.0013) in the postoperative in GPAR and the expiratory reserve volume (ERV) remained (p=0.4446). In the G1stPO, there were significant reductions for: SVC p=<0.0001, ERV p=0.0191, IRV p= 0.0026 and FVC p=<0.0001. Comparing between groups, the SVC (p=0.0027) and FVC (p=0.0028) showed significant difference between the treatments. However, the GPAR showed fewer declines of these capacities. To the ERV (p= 0.1646) and IRV (p=0.3973) there was no significant difference between groups. The atelectasis prevalence was 10% for the GPAR and 30% for G1stPO, with significant difference between the proportions (p = 0.0027). The lowest reduction in SVC and FVC happens when positive pressure is applied in PAR. Thus, the use of BIPAP in the PAR can promote a restoration of ERV and contribute to the reduction of atelectasis. FAPESP 2013/06334-8.

Keywords: atelectasis, bariatric surgery, physiotherapy, pulmonary function, positive pressure

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Authors: R. Al-Dujele, K. A. Cashell

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A tubular flange girder is an I-shaped steel girder with either one of both of the usual flat flange plates replaced with a hollow section. Typically, these hollow sections are either rectangular or circular in shape. Concrete filled tubular flange girders (CFTFGs) are unconventional I-shaped beams that use a hollow structural section as the top flange which is filled with concrete. The resulting section offers very high lateral torsional buckling strength and stiffness compared with conventional steel I-beams of similar depth, width and weight, typically leading to a reduction in lateral bracing requirements. This paper is focussed on investigating the ultimate capacity of concrete filled rectangular tubular flange girders (CFRTFGs). These are complex members and their behaviour is governed by a number of inter-related parameters. The FE model is developed using ABAQUS software, 3-D finite element (FE) model for simply supported CFRTFGs subjected to two point loads applied at the third-span points is built. An initial geometrical imperfection of (L/1000), as well as geometrical and material nonlinearities, are introduced into the model, where L denotes the span of the girder. In this numerical model, the concrete and steel materials are modelled using eight-node solid and four-node shell elements, respectively. In addition to the FE model, simplified analytical expressions for the flexural capacity are also proposed, and the results are compared to those from the FE analyses. The analytical expressions, which are suitable for design, are also shown to be capable of providing an accurate depiction of the bending moment capacity.

Keywords: concrete-filled rectangular tubular flange girders, ultimate capacity, confining effect, finite element analysis

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Authors: Henry Schwartz, Bogdan Iancu, Magnus Gustafsson, Johan Lilius

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The shipping sector generates significant amounts of carbon emissions on annual basis. The excess amount of carbon dioxide is harmful for both the environment and the society, and partly for that reason, there is acute interest to decrease the volume of anthropogenic carbon dioxide emissions in shipping. The usage of the existing cargo carrying capacity can be maximized, and the share of time used in actual transportation operations could be increased if the whole transportation and logistics chain was optimized with the aid of information sharing done through a centralized marketplace and an information-sharing platform. The outcome of this change would be decreased carbon dioxide emission volumes produced per each metric ton of cargo transported by a vessel. Cargo coordination is a platform under development that matches the need for waterborne transportation services with the ships that operate at a given moment in time. In this research, the transition towards adopting cargo coordination is modelled with system dynamics. The model encompasses the complex supply-demand relationships of ship operators and cargo owners. The built scenarios predict the pace at which different stakeholders start using the digitalized platform and by doing so reduce the amount of annual CO2 emissions generated. To improve the reliability of the results, various sensitivity analyses considering the pace of transition as well as the overall impact on the environment (carbon dioxide emissions per amount of cargo transported) are conducted. The results of the study can be used to support investors and politicians in decision making towards more environmentally sustainable solutions. In addition, the model provides concepts and ideas for a wider discussion considering the paths towards carbon neutral transportation.

Keywords: carbon dioxide emissions, energy efficiency, sustainable transportation, system dynamics

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Authors: Mahshid Hodjat, Maryam Baeeri, Mohammad Amin Rezvanfar, Mohammad Abdollahi

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Ethephon is one of the most widely used plant growth regulator in agriculture that its application has been increased in recent years. The toxicity of organophosphate compounds is mostly attributed to their potent inhibition of acetylcholinesterase and their involvement in neurodegenerative disease. Although there are few reports on butyrylcholinesterase inhibitory role of ethephon, still there is no evidence on neurotoxicity and genotoxicity of this compound. The aim of the current study is to assess the potential genotoxic effect of ethephon using two genotoxic endpoints; γH2AX expression and comet assay on embryonic murine fibroblast. γH2AX serves as an early and sensitive biomarker for evaluating the genotoxic effects of chemicals. Oxidative stress biomarkers, including intracellular reactive oxygen species, lipid peroxidation and antioxidant capacity were also examined. The results showed a significant increase in cell proliferation 24h post-treatment with 10, 40,160µg/ml ethephon. The γH2AX expression and γH2AX foci count per cell were increased at low concentration of ethephon that was concomitant with increased DNA damage break at 40 and 160 µg/ml as illustrated by increased comet tail moment. A significant increase in lipid peroxidation and ROS formation were observed at 160 µg/ml and higher doses. The results showed that low-dose of ethephon promoted cell proliferation while induce DNA damage, raising the possibility of ethephon mutagenicity. Ethephon-induced genotoxic effect of low dose might not related to oxidative damage. However, ethephon was found to increase oxidative stress at higher doses, lead to cellular cytotoxicity. Taken together, all data indicated that ethylene, deserves more attention as a plant regulator with potential genotoxicity for which appropriate control is needed to reduce its usage.

Keywords: ethephon, DNA damage, γH2AX, oxidative stress

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Authors: Kelechi E. Ezeji

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The inclusion of relevant content in curricula of architecture schools is vital for attainment of Computer Aided Design (CAD) proficiency by graduates. Implementing this content involves, among other variables, the presence of competent tutors. Consequently, this study sought to investigate the importance of personnel recruitment for inclusion of content vital to the implementation of CAD in the curriculum for architecture education. This was with a view to developing a framework for appropriate implementation of CAD curriculum. It was focused on departments of architecture in universities in south-east Nigeria which have been accredited by National Universities Commission. Survey research design was employed. Data were obtained from sources within the study area using questionnaires, personal interviews, physical observation/enumeration and examination of institutional documents. A multi-stage stratified random sampling method was adopted. The first stage of stratification involved random sampling by balloting of the departments. The second stage involved obtaining respondents’ population from the number of staff and students of sample population. Chi Square analysis tool for nominal variables and Pearson’s product moment correlation test for interval variables were used for data analysis. With ρ < 0.5, the study found significant correlation between the number of CAD literate academic staff and use of CAD in design studio/assignments; that increase in the overall number of teaching staff significantly affected total CAD credit units in the curriculum of the department. The implications of these findings were that for successful implementation leading to attainment of CAD proficiency to occur, CAD-literacy should be a factor in the recruitment of staff and a policy of in-house training should be pursued.

Keywords: computer-aided design, education, personnel recruitment, curriculum

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Authors: S. Mogili, J. S. Kuang, N. Zhang

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Knee joints, the beam column connections found at the roof level of a moment resisting frame buildings, are inherently different from conventional interior and exterior beam column connections in the way that forces from adjoining members are transferred into joint and then resisted by the joint. A knee connection has two distinct load resisting mechanisms, each for closing and opening actions acting simultaneously under reversed cyclic loading. In spite of many distinct differences in the behaviour of shear resistance in knee joints, there are no special design provisions in the major design codes available across the world due to lack of in-depth research on the knee connections. To understand the relative importance of opening and closing actions in design, it is imperative to study knee joints under varying shear stresses, especially at higher opening-to-closing shear stress ratios. Three knee joint specimens, under different input shear stresses, were designed to produce a varying ratio of input opening to closing shear stresses. The design was carried out in such a way that the ratio of flexural strength of beams with consideration of axial forces in opening to closing actions are maintained at 0.5, 0.7, and 1.0, thereby resulting in the required variation of opening to closing joint shear stress ratios among the specimens. The behaviour of these specimens was then carefully studied in terms of closing and opening capacities, hysteretic behaviour, and envelope curves to understand the differences in joint performance based on which an attempt to suggest design guidelines for knee joints is made emphasizing the relative importance of opening and closing actions. Specimens with relatively higher opening stresses were observed to be more vulnerable under the action of seismic loading.

Keywords: Knee-joints, large-scale testing, opening and closing shear stresses, seismic performance

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Authors: Larry Turkish

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Introduction: The NBA is an example of mediocrity and this will be evident in the following paper. The study examines and evaluates the characteristics of the NBA champions. As divisions and playoff teams increase, there is an increase in the probability that the champion originates from the mediocre category. Since it’s inception in 1947, the league has been mediocre and continues to this day. Why does a professional league allow any team with a less than 50% winning percentage into the playoffs? As long as the finances flow into the league, owners will not change the current algorithm. The objective of this paper is to determine if the regular season has meaning in finding an NBA champion. Statistical Analysis: The data originates from the NBA website. The following variables are part of the statistical analysis: Rank, the rank of a team relative to other teams in the league based on the regular season win-loss record; Winning Percentage of a team based on the regular season; Divisions, the number of divisions within the league and Playoff Teams, the number of playoff teams relative to a particular season. The following statistical applications are applied to the data: Pearson Product-Moment Correlation, Analysis of Variance, Factor and Regression analysis. Conclusion: The results indicate that the divisional structure and number of playoff teams results in a negative effect on the winning percentage of playoff teams. It also prevents teams with higher winning percentages from accessing the playoffs. Recommendations: 1. Teams that have a winning percentage greater than 1 standard deviation from the mean from the regular season will have access to playoffs. (Eliminates mediocre teams.) 2. Eliminate Divisions (Eliminates weaker teams from access to playoffs.) 3. Eliminate Conferences (Eliminates weaker teams from access to the playoffs.) 4. Have a balanced regular season schedule, (Reduces the number of regular season games, creates equilibrium, reduces bias) that will reduce the need for load management.

Keywords: alignment, mediocrity, regression, z-score

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Authors: W. Linthicum-Blackhorse, P. Martens

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This present study seeks to discover attitudinal commonalities and differences within a musician population relative to the communication of emotion via music. We hypothesized that instrument type, as well as age and gender, would bear significantly on musicians’ opinions. A survey was administered to 178 participants; 152 were current music majors (mean age 20.3 years, 62 female) and 26 were adult participants in a community choir (mean age 54.0 years, 12 female). The adult participants were all vocalists, while student participants represented the full range of orchestral instruments. The students were grouped by degree program, (performance, music education, or other) and instrument type (voice, brass, woodwinds, strings, percussion). The survey asked 'How important are each of the following areas to you for portraying emotion in music?' Participants were asked to rate each of 15 items on a scale of 1 (not at all important) to 10 (very important). Participants were also instructed to leave blank any item that they did not understand. The 15 items were: dynamic contrast, overall volume, phrasing, facial expression, staging (placement), pitch accuracy, tempo changes, bodily movement, your mood, your attitude, vibrato, rubato, stage/room lighting, clothing type, and clothing color. Contrary to our hypothesis, there was no overall effect of gender or age, and neither did any single response item show a significant difference due to these subject parameters. Among the student participants, however, one-way ANOVA revealed a significant effect of degree program on the rated importance of four items: dynamic contrast, tempo changes, vibrato, and rubato. Significant effects of instrument type were found in the responses to eight items: facial expression, staging, body movement, vibrato, rubato, lighting, clothing type, and clothing color. Post hoc comparisons (Tukey) show that some variation follows from obvious differences between instrument types (e.g. string players are more concerned with vibrato than everyone but woodwind players; vocalists are significantly more concerned with facial expression than everyone but string players), but other differences could point to communal mindsets toward vicarious cues within instrument type. These mindsets could be global (e.g. brass players deeming body movement significantly less important than string players, being less often featured as soloists and appearing less often at the front of the stage) or local (e.g. string players being significantly more concerned than all other groups about both clothing color and type, perhaps due to the strongly-expressed opinions of specific teachers). Future work will attempt to identify the source of these self-appraisals, whether enculturated via explicit pedagogy, or whether absorbed from individuals' observations and performance experience.

Keywords: performance, vicarious cues, communication, emotion

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Authors: Lana Horvat Dmitrović

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The main purpose of this paper is to study the box dimension as fractal property of bifurcations of discrete dynamical systems in higher dimensions. The paper contains the fractal analysis of the orbits near the hyperbolic and non-hyperbolic fixed points in discrete dynamical systems. It is already known that in one-dimensional case the orbit near the hyperbolic fixed point has the box dimension equal to zero. On the other hand, the orbit near the non-hyperbolic fixed point has strictly positive box dimension which is connected to the non-degeneracy condition of certain bifurcation. One of the main results in this paper is the generalisation of results about box dimension near the hyperbolic and non-hyperbolic fixed points to higher dimensions. In the process of determining box dimension, the restriction of systems to stable, unstable and center manifolds, Lipschitz property of box dimension and the notion of projective box dimension are used. The analysis of the bifurcations in higher dimensions with one multiplier on the unit circle is done by using the normal forms on one-dimensional center manifolds. This specific change in box dimension of an orbit at the moment of bifurcation has already been explored for some bifurcations in one and two dimensions. It was shown that specific values of box dimension are connected to appropriate bifurcations such as fold, flip, cusp or Neimark-Sacker bifurcation. This paper further explores this connection of box dimension as fractal property to some specific bifurcations in higher dimensions, such as fold-flip and flip-Neimark-Sacker. Furthermore, the application of the results to the unit time map of continuous dynamical system near hyperbolic and non-hyperbolic singularities is presented. In that way, box dimensions which are specific for certain bifurcations of continuous systems can be obtained. The approach to bifurcation analysis by using the box dimension as specific fractal property of orbits can lead to better understanding of bifurcation phenomenon. It could also be useful in detecting the existence or nonexistence of bifurcations of discrete and continuous dynamical systems.

Keywords: bifurcation, box dimension, invariant manifold, orbit near fixed point

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Authors: Mariana Anaya Villafana

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The sudden change of a significant percentage of the Latino community in the United States elections towards a Republican political orientation was reflected during the 2016 presidential election. This moment represented a radical change that is happening inside the Latino community in the United States, the support they have given to Trump's campaign only demonstrates their support for new anti-immigration regulations and conservative values, which are causing a division of ideologies inside the Latino community. One of the main goals of the following research is to understand the whole phenomenon 'Why would people join their own oppressor?' Align themselves with the politics that prevent many of their relatives to come to the United States and made the assimilation process difficult for their parents. It is important to prove that a change in the identity has happened, through the use of power relations and the attachment to the desired object. A group of Hispanics/Latinos have decided to vote for Trump in order to belong to a society that hasn’t been able to fully include them within it, an action that can result on the non-intentional harm of the values and aims of the rest of the Latino/Hispanic community. In order to understand their new political beliefs, it is necessary to use the method of discourse analysis to comprehend those comments and interviews that are published on web sites such as: 'Latinos for Trump' and 'GOP Hispanic Division'. Among the results that the research has shown, the notion of the 'American Dream' can be considered as a determinant object for the construction of a new identity that is rooted in hard work and legality. One that is proud of the Latino heritage but still wants to maintain the boundaries between legality and illegality in relation to the immigrants. This discourse results on a contradiction to most of the cases because they mention that their families came to the U.S. as immigrants; the only difference is that they work hard to obtain legal citizenship.

Keywords: populism, identity, Latino Community, migration

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Authors: Sepinoud Hamedi

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The ponder points to observationally look at the impact of carbon-neutrality approaches on the key assets required for Industry 4.0 driven savvy fabricating and how these assets can give a economical competitive advantage. The hypothetical system is coordinates with the regulation hypothesis and the resource-based see (RBV). The observational strategy is utilized for collecting information through studies and assist covariance-based auxiliary condition modeling is utilized to test the theories. Discoveries demonstrate that carbon–neutral-based government arrangements have a more grounded impact on unmistakable assets and human aptitudes than intangible assets related to Industry 4.0 driven shrewd fabricating. Moment, carbon–neutral arrangement arrangement with the firm’s maintainability destinations plays a directing impact on the relationship between carbon–neutral-based government arrangements and assets (substantial, intangible assets and human abilities) for Industry 4.0 driven shrewd fabricating. Finally, the three assets (substantial, intangible assets and human abilities) for Industry 4.0 driven savvy fabricating play a basic part in creating firms’ carbon–neutral capability and assist improving operational execution. Administrative suggestions incorporate venture in progressed advanced innovations, creating a solid mentality among workers and supply chain partners, and planning preparing programs for upgrading shrewd fabricating execution to create carbon-neutrality capability. This think about proposes a crossover hypothesis within the setting of carbon nonpartisanship by coordination institutional theory and RBV. Typically the primary think about that looks at the impact of carbon neutrality-based government arrangements on crucial Industry 4.0-driven savvy fabricating assets and the circuitous impact on carbon nonpartisanship capability and operational execution.

Keywords: carbon, industry 4.0, neutrality, RBV, nonpartisanship

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Authors: Abiodun O. Ibude

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Several organizations have devised the strategy of engaging the services of staff not directly employed by them in their production and service delivery. Some organizations also engage on contracting another organization to carry out a part of service or production process on their behalf. Outsourcing is becoming an important alternative employment option for most organizations. This paper attempts an exposition on the rights of workers within the more specific context of outsourcing as a human resource management phenomenon. Outsourced employees and their rights are treated conceptually and analytically in a generic sense as a mere subset of the larger whole, that is, labor. Outsourced employees derive their rights, like all workers, from their job context as well as the legal environment (municipal and global) in which they operate. The dynamics of globalization and the implications of this development for labor practices receive considerable attention in this exposition. In this regard, a guarded proposition is made, to examine the practice and effect of engaging outsourcing as an economic decision designed primarily to cut down on operational costs rather than a Human Resources Management decision to improve worker welfare. The population of the study was selected from purposive and simple random sampling techniques. Data obtained were analyzed through a simple percentage, Pearson product-moment correlation, and cross-tabulation. From the research conducted, it was discovered that, although outsourcing possesses opportunities for organizations, there are drawbacks arising from its implementation of job securities. It was also discovered that some employees are being exploited through this strategy. This gives rise to lower motivation and thereby decline in performance. In conclusion, there is need for examination of Human Resource Managers’ strategies that can serve as management policy tools for the protection of the rights of outsourced employees.

Keywords: legal environment, operational cost, outsourcing, protection

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Authors: Vivian Caroline Koerbel Dombrowski

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Armed conflicts have always meant the ultimate expression of power and at the same time, lack of understanding among nations. Cities were destroyed, people were killed, assets were devastated. But these are not only the loss of a war: the environmental damage comes to be considered immeasurable losses in the short, medium and long term. And this is because no nation wants to bear that cost. They invest in military equipment, training, technical equipment but the environmental account yet finds gaps in international law. Considering such a generalization in rights protection, many nations are at imminent danger in a conflict if the water will be used as a mass weapon, especially if we consider important rivers such as Jordan, Euphrates and Nile. The top three international documents were analyzed on the subject: the Stockholm Convention (1972), Additional Protocol I to the Geneva Convention (1977) and the Rome Statute (1998). Indeed, some references are researched in doctrine, especially scientific articles, to substantiate with consistent data about the extent of the damage, historical factors and decisions which have been successful. However, due to the lack of literature about this subject, the research tends to be exhaustive. From the study of the indicated material, it was noted that international law - humanitarian and environmental - calls in some of its instruments the environmental protection in war conflicts, but they are generic and vague rules that do not define exactly what is the environmental damage , nor sets standards for measure them. Taking into account the mains conflicts of the century XX: World War II, the Vietnam War and the Gulf War, one must realize that the environmental consequences were of great rides - never deactivated landmines, buried nuclear weapons, armaments and munitions destroyed in the soil, chemical weapons, not to mention the effects of some weapons when used (uranium, agent Orange, etc). Extending the search for more recent conflicts such as Afghanistan, it is proven that the effects on health of the civilian population were catastrophic: cancer, birth defects, and deformities in newborns. There are few reports of nations that, somehow, repaired the damage caused to the environment as a result of the conflict. In the pitch of contemporary conflicts, many nations fear that water resources are used as weapons of mass destruction, because once contaminated - directly or indirectly - can become a means of disguised genocide side effect of military objective. In conclusion, it appears that the main international treaties governing the subject mention the concern for environmental protection, however leave the normative specifications vacancies necessary to effectively there is a prevention of environmental damage in armed conflict and, should they occur, the repair of the same. Still, it appears that there is no protection mechanism to safeguard natural resources and avoid them to become a mass destruction weapon.

Keywords: armed conflicts, criminal liability, environmental damages, humanitarian law, mass weapon

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Authors: Masahiro Suzuki, Nobuyuki Okura

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The crosswind effect on ground transportations has been extensively investigated for decades. The effect of tornado, however, has been hardly studied in spite of the fact that even heavy ground vehicles, namely, trains were overturned by tornadoes with casualties in the past. Therefore, aerodynamic effects of the tornado on the train were studied by several approaches in this study. First, an experimental facility was developed to clarify aerodynamic forces acting on a vehicle running through a tornado. Our experimental set-up consists of two apparatus. One is a tornado simulator, and the other is a moving model rig. PIV measurements showed that the tornado simulator can generate a swirling-flow field similar to those of the natural tornadoes. The flow field has the maximum tangential velocity of 7.4 m/s and the vortex core radius of 96 mm. The moving model rig makes a 1/40 scale model train of single-car/three-car unit run thorough the swirling flow with the maximum speed of 4.3 m/s. The model car has 72 pressure ports on its surface to estimate the aerodynamic forces. The experimental results show that the aerodynamic forces vary its magnitude and direction depends on the location of the vehicle in the flow field. Second, the aerodynamic forces on the train were estimated by using Rankin vortex model. The Rankin vortex model is a simple tornado model which widely used in the field of civil engineering. The estimated aerodynamic forces on the middle car were fairly good agreement with the experimental results. Effects of the vortex core radius and the path of the train on the aerodynamic forces were investigated using the Rankin vortex model. The results shows that the side and lift forces increases as the vortex core radius increases, while the yawing moment is maximum when the core radius is 0.3875 times of the car length. Third, a computational simulation was conducted to clarify the flow field around the train. The simulated results qualitatively agreed with the experimental ones.

Keywords: aerodynamic force, experimental method, tornado, train

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Authors: Aya Al Masri, Naima Oubenali, Safoin Aktaou, Thibault Julien, Malorie Martin, Fouad Maaloul

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Introduction: The increased number of performed 'Computed Tomography (CT)' examinations raise public concerns regarding associated stochastic risk to patients. In its Publication 102, the ‘International Commission on Radiological Protection (ICRP)’ emphasized the importance of managing patient dose, particularly from repeated or multiple examinations. We developed a Dose Archiving and Communication System that gives multiple dose indexes (organ dose, effective dose, and skin-dose mapping) for patients undergoing radiological imaging exams. The aim of this study is to compare the organ dose values given by our software for patients undergoing CT exams with those of another software named "VirtualDose". Materials and methods: Our software uses Monte Carlo simulations to calculate organ doses for patients undergoing computed tomography examinations. The general calculation principle consists to simulate: (1) the scanner machine with all its technical specifications and associated irradiation cases (kVp, field collimation, mAs, pitch ...) (2) detailed geometric and compositional information of dozens of well identified organs of computational hybrid phantoms that contain the necessary anatomical data. The mass as well as the elemental composition of the tissues and organs that constitute our phantoms correspond to the recommendations of the international organizations (namely the ICRP and the ICRU). Their body dimensions correspond to reference data developed in the United States. Simulated data was verified by clinical measurement. To perform the comparison, 270 adult patients and 150 pediatric patients were used, whose data corresponds to exams carried out in France hospital centers. The comparison dataset of adult patients includes adult males and females for three different scanner machines and three different acquisition protocols (Head, Chest, and Chest-Abdomen-Pelvis). The comparison sample of pediatric patients includes the exams of thirty patients for each of the following age groups: new born, 1-2 years, 3-7 years, 8-12 years, and 13-16 years. The comparison for pediatric patients were performed on the “Head” protocol. The percentage of the dose difference were calculated for organs receiving a significant dose according to the acquisition protocol (80% of the maximal dose). Results: Adult patients: for organs that are completely covered by the scan range, the maximum percentage of dose difference between the two software is 27 %. However, there are three organs situated at the edges of the scan range that show a slightly higher dose difference. Pediatric patients: the percentage of dose difference between the two software does not exceed 30%. These dose differences may be due to the use of two different generations of hybrid phantoms by the two software. Conclusion: This study shows that our software provides a reliable dosimetric information for patients undergoing Computed Tomography exams.

Keywords: adult and pediatric patients, computed tomography, organ dose calculation, software comparison

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Authors: M. R. Ahmad, I. Musirin, M. M. Othman, N. A. Rahmat

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Plug-in Hybrid-Electric Vehicle (PHEV) has gained immense popularity in recent years. PHEV offers numerous advantages compared to the conventional internal-combustion engine (ICE) vehicle. Millions of PHEVs are estimated to be on the road in the USA by 2020. Uncoordinated PHEV charging is believed to cause severe impacts to the power grid; i.e. feeders, lines and transformers overload and voltage drop. Nevertheless, improper PHEV data model used in such studies may cause the findings of their works is in appropriated. Although smart charging is more attractive to researchers in recent years, its implementation is not yet attainable on the street due to its requirement for physical infrastructure readiness and technology advancement. As the first step, it is finest to study the impact of charging PHEV based on real vehicle travel data from National Household Travel Survey (NHTS) and at present charging rate. Due to the lack of charging station on the street at the moment, charging PHEV at home is the best option and has been considered in this work. This paper proposed a technique that comprehensively presents the impact of charging PHEV on power system networks considering huge numbers of PHEV samples with its traveling data pattern. Vehicles Charging Load Profile (VCLP) is developed and implemented in IEEE 30-bus test system that represents a portion of American Electric Power System (Midwestern US). Normalization technique is used to correspond to real time loads at all buses. Results from the study indicated that charging PHEV using opportunity charging will have significant impacts on power system networks, especially whereas bigger battery capacity (kWh) is used as well as for higher penetration level.

Keywords: plug-in hybrid electric vehicle, transportation electrification, impact of charging PHEV, electricity demand profile, load profile

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Authors: Akbar Jamali

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Many scholars consider Hegel’s philosophy of art as the greatest theory of aesthetics since Aristotle’s Poetics. ‘Freedom’ distinguishes modern, especially German Idealism with Greek philosophy. Therefore, introducing and contemplating on Hegel’s Aesthetics as a whole, freedom as the essence of art, Hegel’s controversial claim on the end of art, and the relation of art and state is the main theme of this study. Hegel’s aesthetics is to be understood in his whole system. According to Hegel’s speculative philosophy, being is to be understood as self-determining Reason or Idea. The self-determining Reason actualizes and realizes himself in the course of history. Idea in the process of self-actualization becomes more and more rational. It first actualizes itself in matter, then in non-conscious life, finally in conscious and self-conscious life. Self-conscious life is the most rational stage of development of Idea in which the subject can think and imagine, use language and exercise freedom. Hegel calls this self-conscious life Spirit (Geist). Therefore, emergence of human being is an essential moment in the process of self-determination of Reason. It is not accidental rather a necessity. The essence of spirit is freedom. Since the history is the process of the self-actualization if spirit, humankind becomes more and more, free. Spirit in its ‘Absolute’ form manifests itself into three forms; Art, Religion and philosophy. Art is the first stage in which Spirit understands itself. In fact, Art is the expression of human spirit, which is comprehended by our senses. Beauty is defined as the sensuous expression of free Spirit. The purpose of art is, therefore, to express, enjoy and contemplate on our freedom. State belongs to the realm of Objective spirit, while Art along with Religion and philosophy belong to the realm of Absolute Spirit. Absolute spirit is superior to Objective Spirit; therefore, state must not interfere in the realm of art. Limitation on art by state directly violates freedom and prevents development of national spirit. Genuine art leads us to freedom and richness of (national) Spirit. Using Hegel’s philosophy of art, we can comprehend why totalitarian states try to limit art and, why artists are the enemy of totalitarian states. In this philosophical system, we contemplate on art as a way to freedom and emancipation.

Keywords: aesthetics, freedom, spirit, state

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Authors: Vidula Shevade, B. J. Nagare, Sajeev Chacko

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First principles simulation, meaning density functional theory (DFT) calculations with plane waves and pseudopotential, has become a prized technique in condensed matter theory. Nanoparticles (NP) have been known to possess good catalytic activities, especially for molecules such as CO, O₂, etc. Among the metal NPs, Aluminium based NPs are also widely known for their catalytic properties. Aluminium metal is a lightweight, excellent electrical, and thermal abundant chemical element in the earth’s crust. Aluminium NPs, when added to solid rocket fuel, help improve the combustion speed and considerably increase combustion heat and combustion stability. Adding aluminium NPs into normal Al/Al₂O₃ powder improves the sintering processes of the ceramics, with high heat transfer performance, increased density, and enhanced thermal conductivity of the sinter. We used VASP and Gaussian 0₃ package to compute the geometries, electronic structure, and bonding properties of Al₁₂Ni as well as its interaction with O₂ and CO molecules. Several MD simulations were carried out using VASP at various temperatures from which hundreds of structures were optimized, leading to 24 unique structures. These structures were then further optimized through a Gaussian package. The lowest energy structure of Al₁₂Ni has been reported to be a singlet. However, through our extensive search, we found a triplet state to be lower in energy. In our structure, the Ni atom is found to be on the surface, which gives the non-zero magnetic moment. Incidentally, O2 and CO molecules are also triplet in nature, due to which the Al₁₂-Ni cluster is likely to facilitate the oxidation process of the CO molecule. Our results show that the most favourable site for the CO molecule is the Ni atom and that for the O₂ molecule is the Al atom that is nearest to the Ni atom. Al₁₂Ni-O₂ and Al₁₂-Ni-CO structures we extracted using VMD. Al₁₂Ni nanocluster, due to in triplet electronic structure configuration, indicates it to be a potential candidate as a catalyst for oxidation of CO molecules.

Keywords: catalyst, gaussian, nanoparticles, oxidation

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Authors: Ndarusanze Berchmans

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This research work focused on the analysis of the observations of tuberculous meningitis in HIV-positive patients who were treated by the Prince Regent Charles Hospital in Bujumbura. A number of 246 seropositive patients were examined by the laboratory of Prince Regent Charles in the period between 2010 and 2015. We did a retrospective study; we used data from the registers of the laboratories mentioned above; the objective was to approach the epidemiological, biological, clinical, and therapeutic characteristics of tuberculosis meningitis infection: 124 women (50.40% of AIDS patients) and 122 men (49.59% of AIDS patients) were subject to the diagnosis by identification of cerebrospinal fluid (CSF). The average age of the patients was 30 years for this period. The population at risk has an average age of between 34 and 42 years for the years between 2010-2015. From 2010 to 2012, cases of opportunistic diseases (e.g., tuberculous meningitis and Cryptococcus neoformans meningitis), often found in immunocompromised, were observed at a high rate; in this period, there was a disturbance of the rhythm providing antiretroviral drugs to people with AIDS. The rate of the two meningitis (tuberculous meningitis and Cryptococcus neoformans meningitis) remained above 10% to gradually decrease until 2015, with the gradual return of antiretrovirals. This period records an overall average of 25 cases of tuberculous meningitis, or a percentage of 10.16%. For the year 2015, there were 4 cases of tuberculous meningitis out of a total of 35 seropositive examined (11.42%). This year's percentage shows that the number of tuberculous meningitis cases has fallen from the rate in previous years. This is the result of the care given by associations against HIV/AIDS to HIV-positive people. This decrease in cases of tuberculous meningitis is due to the acquisition of antiretrovirals by all HIV-positive people treated by hospitals. For the moment, these hospitals are taking care of many AIDS patients by providing them permanently with antiretrovirals; Besides that, there are many patients who are supported by associations whose activities are directed against HIV/AIDS.

Keywords: Cryptococcus neoformans meningitis, tuberculosis meningitis, neurological complications, epidemiology of meningitis

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Authors: Muhammad R. Bello, Mamman A. Wasagu, Yahya M. Kamar

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The study investigated the effects of computer-aided instructional package (CAIP) on performance and retention of genetic concepts among secondary school students in Niger State. Quasi-experimental research design i.e. pre-test-post-test experimental and control groups were adopted for the study. The population of the study was all senior secondary school three (SS3) students’ offering biology. A sample of 223 students was randomly drawn from six purposively selected secondary schools. The researchers’ developed computer aided instructional package (CAIP) on genetic concepts was used as treatment instrument for the experimental group while the control group was exposed to the conventional lecture method (CLM). The instrument for data collection was a Genetic Performance Test (GEPET) that had 50 multiple-choice questions which were validated by science educators. A Reliability coefficient of 0.92 was obtained for GEPET using Pearson Product Moment Correlation (PPMC). The data collected were analyzed using IBM SPSS Version 20 package for computation of Means, Standard deviation, t-test, and analysis of covariance (ANCOVA). The ANOVA analysis (Fcal (220) = 27.147, P < 0.05) shows that students who received instruction with CAIP outperformed the students who received instruction with CLM and also had higher retention. The findings also revealed no significant difference in performance and retention between male and female students (tcal (103) = -1.429, P > 0.05). It was recommended amongst others that teachers should use computer-aided instructional package in teaching genetic concepts in order to improve students’ performance and retention in biology subject. Keywords: Computer-aided Instructional Package, Performance, Retention and Genetic Concepts.

Keywords: computer aided instructional package, performance, retention, genetic concepts, senior secondary school students

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Authors: Tom Hickey

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It is difficult to conceive of a case that might more starkly bring the arguments concerning judicial review to the fore than State (Ryan) v Lennon. Small wonder that it has attracted so much scholarly attention, although the fact that almost all of it has been in an Irish setting is perhaps surprising, given the illustrative value of the case in respect of a philosophical quandary that continues to command attention in all developed constitutional democracies. Should judges have power to invalidate legislation? This article revisits Ryan v Lennon with an eye on the importance of the idea of “democracy” in the case. It assesses the meaning of democracy: what its purpose might be and what practical implications might follow, specifically in respect of judicial review. Based on this assessment, it argues for a particular institutional model for the vindication of constitutional rights. In the context of calls for the drafting of a new constitution for Ireland, however forlorn these calls might be for the moment, it makes a broad and general case for the abandonment of judicial supremacy and for the taking up of a model in which judges have a constrained rights reviewing role that informs a more robust role that legislators would play, thereby enhancing the quality of the control that citizens have over their own laws. The article is in three parts. Part I assesses the exercise of judicial power over legislation in Ireland, with the primary emphasis on Ryan v Lennon. It considers the role played by the idea of democracy in that case and relates it to certain apparently intractable dilemmas that emerged in later Irish constitutional jurisprudence. Part II considers the concept of democracy more generally, with an eye on overall implications for judicial power. It argues for an account of democracy based on the idea of equally shared popular control over government. Part III assesses how this understanding might inform a new constitutional arrangement in the Irish setting for the vindication of fundamental rights.

Keywords: constitutional rights, democracy as popular control, Ireland, judicial power, republican theory, Ryan v Lennon

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Authors: Gelacio JuáRez-Luna, Daniel Enrique GonzáLez-RamíRez, Enrique Tenorio-Montero

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Frame elements coupled with springs elements are used for modelling the development of hinges in segmented tunnels, the spring elements modelled the rotational, transversal and axial failure. These spring elements are equipped with constitutive models to include independently the moment, shear force and axial force, respectively. These constitutive models are formulated based on damage mechanics and experimental test reported in the literature review. The mesh of the segmented tunnels was discretized in the software GID, and the nonlinear analyses were carried out in the finite element software ANSYS. These analyses provide the capacity curve of the primary and secondary lining of a segmented tunnel. Two numerical examples of segmented tunnels show the capability of the spring elements to release energy by the development of hinges. The first example is a segmental concrete lining discretized with frame elements loaded until hinges occurred in the lining. The second example is a tunnel with primary and secondary lining, discretized with a double ring frame model. The outer ring simulates the segmental concrete lining and the inner ring simulates the secondary cast-in-place concrete lining. Spring elements also modelled the joints between the segments in the circumferential direction and the ring joints, which connect parallel adjacent rings. The computed load vs displacement curves are congruent with numerical and experimental results reported in the literature review. It is shown that the modelling of a tunnel with primary and secondary lining with frame elements and springs provides reasonable results and save computational cost, comparing with 2D or 3D models equipped with smeared crack models.

Keywords: damage, hinges, lining, tunnel

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Authors: Jingcheng Ma, Patricia B. Weisensee, Young H. Shin, Yujin Chang, Junjiao Tian, William P. King, Nenad Miljkovic

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Water droplet impact on surfaces is a ubiquitous phenomenon in both nature and industry. The transfer of mass, momentum and energy can be influenced by the time of contact between droplet and surface. In order to reduce the contact time, we study the influence of substrate motion prior to impact on the dynamics of droplet recoil. Using optical high speed imaging, we investigated the impact dynamics of macroscopic water droplets (~ 2mm) on rigid nanostructured superhydrophobic surfaces vibrating at 60 – 300 Hz and amplitudes of 0 – 3 mm. In addition, we studied the influence of the phase of the substrate at the moment of impact on total contact time. We demonstrate that substrate vibration can alter droplet dynamics, and decrease total contact time by as much as 50% compared to impact on stationary rigid superhydrophobic surfaces. Impact analysis revealed that the vibration frequency mainly affected the maximum contact time, while the amplitude of vibration had little direct effect on the contact time. Through mathematical modeling, we show that the oscillation amplitude influences the possibility density function of droplet impact at a given phase, and thus indirectly influences the average contact time. We also observed more vigorous droplet splashing and breakup during impact at larger amplitudes. Through semi-empirical mathematical modeling, we describe the relationship between contact time and vibration frequency, phase, and amplitude of the substrate. We also show that the maximum acceleration during the impact process is better suited as a threshold parameter for the onset of splashing than a Weber-number criterion. This study not only provides new insights into droplet impact physics on vibrating surfaces, but develops guidelines for the rational design of surfaces to achieve controllable droplet wetting in applications utilizing vibration.

Keywords: contact time, impact dynamics, oscillation, pear-shape droplet

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Authors: Nesreddine Djafar Henni, Akram Khelaifia, Salah Guettala, Rachid Chebili

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Reinforced concrete shear walls and vertical plate-like elements play a pivotal role in efficiently managing a building's response to seismic forces. This study investigates how the performance of reinforced concrete buildings equipped with shear walls featuring different shear wall-to-frame stiffness ratios aligns with the requirements stipulated in the Algerian seismic code RPA99v2003, particularly in high-seismicity regions. Seven distinct 3D finite element models are developed and evaluated through nonlinear static analysis. Engineering Demand Parameters (EDPs) such as lateral displacement, inter-story drift ratio, shear force, and bending moment along the building height are analyzed. The findings reveal two predominant categories of induced responses: force-based and displacement-based EDPs. Furthermore, as the shear wall-to-frame ratio increases, there is a concurrent increase in force-based EDPs and a decrease in displacement-based ones. Examining the distribution of shear walls from both force and displacement perspectives, model G with the highest stiffness ratio, concentrating stiffness at the building's center, intensifies induced forces. This configuration necessitates additional reinforcements, leading to a conservative design approach. Conversely, model C, with the lowest stiffness ratio, distributes stiffness towards the periphery, resulting in minimized induced shear forces and bending moments, representing an optimal scenario with maximal performance and minimal strength requirements.

Keywords: dual RC buildings, RC shear walls, modeling, static nonlinear pushover analysis, optimization, seismic performance

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