Search results for: Kaduna State University

Authors: A. Mohammadi, S. Asghari, M. Aien, M. Rashidinejad

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After emergent of alternative current networks and their popularity, asynchronous motors became more widespread than other kinds of industrial motors. In order to control and run these motors efficiently, an accurate estimation of motor parameters is needed. There are different methods to obtain these parameters such as rotor locked test, no load test, DC test, analytical methods, and so on. The most common drawback of these methods is their inaccuracy in estimation of some motor parameters. In order to remove this concern, a novel method for parameter estimation of induction motors using particle swarm optimization (PSO) algorithm is proposed. In the proposed method, transient state of motor is used for parameter estimation. Comparison of the simulation results purtuined to the PSO algorithm with other available methods justifies the effectiveness of the proposed method.

Keywords: induction motor, motor parameter estimation, PSO algorithm, analytical method

Procedia PDF Downloads 618

Authors: Konstantza Tonova, Ivan Svinyarov, Milen G. Bogdanov

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Ionic liquids consisting of pairs of imidazolium or phosphonium cation and chloride or saccharinate anion were synthesized and compared with respect to their extraction efficiency towards the fermentative L-lactic acid. The acid partitioning in the equilibrated biphasic systems of ionic liquid and water was quantified through the extraction degree and the partition coefficient. The water transfer from the aqueous into the ionic liquid-rich phase was also always followed. The effect of pH, which determines the state of lactic acid in the aqueous source was studied. The effect of other salting-out substances that modify the ionic liquid/water equilibrium was also investigated in view to reveal the best liquid-liquid system with respect to low toxicity, high extraction and back extraction efficiencies and performance simplicity.

Keywords: ionic liquids, biphasic system, extraction, lactic acid

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Authors: Digby Warren, Jiri Kropac

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This comparative study seeks to develop a deeper understanding of what is meant by “education for social justice” (ESJ) - an aspiration articulated by universities, though often without much definition. The research methodology involved thematic analysis of data from in-depth interviews with academics (voluntary participants) in different disciplines and institutions in the UK, Czech Republic and other EU countries. The interviews explored lecturers’ conceptions of ESJ, their practice of it, and associated challenges and enabling factors. Main findings are that ESJ is construed as provision of equitable and conscientising education opportunities that run across the whole higher education (HE) journey, from widening access to HE to stimulating critical learning and awareness that can empower graduates to transform their lives and societies. Teaching practice featured study of topics related to social justice; collaborative and creative learning activities, and assignments offering choice and connection to students’ realities. Student responses could be mixed, occasionally resistant, but mostly positive in terms of gaining increased confidence and awareness of equality and social responsibility. Influences at the macro, meso and mico level could support or limit scope for ESJ. Overall, the study highlights the strong, values-based commitment of HE teachers to facilitating student learning engagement, wellbeing and development towards building a better world.

Keywords: higher education, social justice, inclusivity, diversity

Procedia PDF Downloads 65

Authors: M. Hadji, A. Haddad, Y. Hadji

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The effects of boronizing treatment on the friction coefficient and wear behavior of 0.35 Vf TiC- Ti3 SiC2 composite were investigated. In order to modify the surface properties of Ti3SiC2, boronizing treatment was carried out through powder pack cementation in the 1150-1350 °C temperature range. After boronizing treatment, one mixture layer, composed of TiB2 and SiC, forms on the surface of Ti3SiC2. The growth of the coating is processed by inward diffusion of Boron and obeys a linear rule. The Boronizing treatment increases the hardness of Ti3SiC2 from 6 GPa to 13 GPa. In the pin-on-disc test, i twas found that the material undergoes a steady-state coefficient of friction of around 0.8 and 0.45 in case of Ti3SiC2/Al2O3 tribocouple under 7 N load for the non treated and the boronized samples, respectively. The wear resistance of Ti3SiC2 under Al2O3 ball sliding has been significantly improved, which indicated that the boronizing treatment is a promising surface modification way of Ti3SiC2.

Keywords: MAX phase, boronizing, hardness, wear

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Authors: Wisu Suntoyo, Dedy Sushandoyo

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Innovation and digital transformation are essential for firms’ competitiveness in the digital age. The competition in Indonesia’s banking industry provides an intriguing case study for understanding how digital transformation can generate innovation in established companies. The empirical evidence of this study is mainly based on interviews and annual reports examining four established banks in their various states of digital transformation. The findings of this study reveal that banks’ digital transformations that lead to innovations differ in terms of the activities undertaken and the outcomes achieved depending on the state of advancement in which they are. Digital transformation is a complex and challenging process, and this study finds that with this strategy, established banks have shown capable of generating innovation. Banks can choose types of transformation activities that generate radical, architectural, modular, or even incremental innovations.

Keywords: digital transformation, innovations, banking industry, established banks

Procedia PDF Downloads 80

Authors: Dong Jin Kang

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Application of single board microcontrollers is an important skill even for non-electronic engineering major students. Arduino board is widely utilized in engineering classes of the Yeungnam University of South Korea. In those classes, students are subjected to learn how to use various sensor components related to motion, sound, light, and so on as well as physical quantities. Students are grouped into several teams, and each team consists of 4~5 students. Many students are not motivated enough to learn those skills. An extracurricular program was planned to improve this problem. The extracurricular program was held as an international boot camp where students from three different countries were invited to participate. 10 students groups were formed, and each team was consisted of students having different nationality. The camp was 4 days long and wrapped up with competitions. During the camp, every student was assigned to design and make a two wheel robot. The competition was carried out in two different areas; individual and group performances. As most skills dealt in the class are used to build the robot, students are much motivated to review the whole subjects of the class. All students were surveyed after the program. The survey shows that the skills studied in the class are greatly improved, and practically understood. Staying at the dormitory and teaming with international students are help students improve communication skills. Competition at the camp was found as a key element to inspire and attract students for voluntary participation.

Keywords: extracurricular program, robot, Arduino board, international camp, competition

Procedia PDF Downloads 207

Authors: Dalibor Štys, Kryštof M. Stys, Maryia Chkalova, Petr Kouba, Aliaxandr Pautsina, Dalibor Štys Jr., Jana Pečenková, Denis Durniev, Tomáš Náhlík, Petr Císař

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In this article, a construction and some properties of the 5iD viewer, the system recording simultaneously five views of a given experimental object is reported. Properties of the system are demonstrated on the analysis of fish schooling behavior. It is demonstrated the method of instrument calibration which allows inclusion of image distortion and it is proposed and partly tested also the method of distance assessment in the case that only two opposite cameras are available. Finally, we demonstrate how the state trajectory of the behavior of the fish school may be constructed from the entropy of the system.

Keywords: 3D positioning, school behavior, distance calibration, space vision, space distortion

Procedia PDF Downloads 375

Authors: Ali Oublal

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If any period in history seems appropriate for the study of identity, it is a period of greater mobility; the 21st century. Margaret Wetherill (2009) is thus right while asking who we can be in this age. New biographies of people, their trajectories and new locations appear on the ground; how people do make sense of the self becomes the central question not only for social scientists, and cultural theorists but also for literary critics. New-fangled technologies have resulted in the substitution of stable identities by multiple, fragmented and more uncertain identities. A liquid sense of the self as well as unstable and dynamic forms of life does not fail to inspire novelists who have given robust sense of identities attributed to their characters. The following account comes to snapshot features of identity as being presented by meta-modernist novels: the sympathizer, sisters and a girl is a half formed thing. It is a stance that refutes the claim of Elliott‘s who still adheres the stable state of identity in meta-modernist age while reconciling the two paradigms modernity and postmodernity.

Keywords: identity, metamodernism, fragmantation, stability, literature

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Authors: Elvis Nyirenda

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This research study work was done to evaluate and propose an optimum measure to enhance the uptake of clean energy technologies such as solar photovoltaics, the study also aims at enhancing the country’s energy mix from the overdependence on hydro power which is susceptible to droughts and climate change challenges The country in the years 2015 - 2016 and 2018 - 2019 had received rainfall below average due to climate change and a shift in the weather pattern; this resulted in prolonged power outages and load shedding for more than 10 hours per day. ZESCO Limited, the utility company that owns infrastructure in the generation, transmission, and distribution of electricity (state-owned), is seeking alternative sources of energy in order to reduce the over-dependence on hydropower stations. One of the alternative sources of energy is Solar Energy from the sun. However, solar power is intermittent in nature and to smoothen the load curve, investment in robust energy storage facilities is of great importance to enhance security and reliability of electricity supply in the country. The methodology of the study looked at the historical performance of the Kafue gorge upper power station and utilised the hourly generation figures as input data for generation modelling in Homer software. The average yearly demand was derived from the available data on the system SCADA. The two dams were modelled as natural battery with the absolute state of charging and discharging determined by the available water resource and the peak electricity demand. The software Homer Energy System is used to simulate the scheme incorporating a pumped storage facility and Solar photovoltaic systems. The pumped hydro scheme works like a natural battery for the conservation of water, with the only losses being evaporation and water leakages from the dams and the turbines. To address the problem of intermittency on the solar resource and the non-availability of water for hydropower generation, the study concluded that utilising the existing Hydro power stations, Kafue Gorge upper and Kafue Gorge Lower to work conjunctively with Solar energy will reduce power deficits and increase the security of supply for the country. An optimum capacity of 350MW of solar PV can be integrated while operating Kafue Gorge power station in both generating and pumping mode to enable efficient utilisation of water at Kafue Gorge upper Dam and Kafue Gorge Lower dam.

Keywords: hydropower, solar power systems, energy storage, photovoltaics, solar irradiation, pumped hydro storage system, supervisory control and data acquisition, Homer energy

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Authors: Sana El-Azzeh, Farraj Al-Ajmi, Abdulrahman Al-Aqqad, Mohamed Salem

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Thermal comfort is defined according to ANSI/ASHRAE Standard 55 as a condition of mind that expresses satisfaction with the thermal environment and is assessed by subjective evaluation. Sustaining this standard of thermal comfort for occupants of buildings or other enclosures is one of the important goals of HVAC design engineers. This paper presents a study of thermal comfort and adaptive behaviors of occupants who occupies two locations at the campus of the Australian College of Kuwait. A longitudinal survey and field measurement were conducted to measure thermal comfort, adaptive behaviors, and indoor environment qualities. The study revealed that female occupants in the selected locations felt warmer than males and needed more air velocity and lower temperature.

Keywords: indoor thermal comfort, educational facility, gender analysis, dry desert climate

Procedia PDF Downloads 141

Authors: Gyu-Jin Kim, Hyo-Gyoung Kwak

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In this research, the effect of prestressing force on the nonlinearity of concrete was investigated by an experimental study. For the measurement of ultrasonic nonlinearity, a prestressed concrete beam was prepared and a nonlinear resonant ultrasound method was adopted. When the prestressing force changes, the stress state of the concrete inside the beam is affected, which leads to the occurrence of micro-cracks and changes in mechanical properties. Therefore, it is necessary to introduce nonlinear ultrasonic technology which sensitively reflects microstructural changes. Repetitive prestressing load history, including maximum levels of 45%, 60% and 75%, depending on the compressive strength, is designed to evaluate the impact of loading levels on the nonlinearity. With the experimental results, the possibility of ultrasonic nonlinearity as a trial indicator of stress was evaluated.

Keywords: micro crack, nonlinear ultrasonic resonant spectroscopy, prestressed concrete beam, prestressing force, ultrasonic nonlinearity

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Authors: I. Muslih, A. Alkhalailah, A. Merdji

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Photovoltaic efficiency is highly affected by dust accumulation; the dust particles prevent direct solar radiation from reaching the panel surface; therefore a reduction in output power will occur. A study of dust and soiling accumulation effect on the output power of PV panels was conducted for different periods of time from May to October in three countries of the MENA region, Jordan, Egypt, and Algeria, under local weather conditions. This study leads to build a more realistic equation to estimate the power reduction as a function of time. This logarithmic function shows the high reduction in power in the first days with 10% reduction in output power compared to the reference system, where it reaches a steady state value after 60 days to reach a maximum value of 30%.

Keywords: dust effect, MENA, solar energy, PV system

Procedia PDF Downloads 206

Authors: S. H. Atef, N. H. Mahmoud, S. Abdrahman, A. Fattoh

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Background: The aim of the study is to assess the diagnostic value of fibrotest and hyaluronic acid in discriminate between insignificant and significant fibrosis. Also, to find out if these parameters could replace liver biopsy which is currently used for selection of chronic hepatitis C patients eligible for antiviral therapy. Study design: This study was conducted on 52 patients with HCV RNA detected by polymerase chain reaction (PCR) who had undergone liver biopsy and attending the internal medicine clinic at Ain Shams University Hospital. Liver fibrosis was evaluated according to the METAVIR scoring system on a scale of F0 to F4. Biochemical markers assessed were: alpha-2 macroglobulin (α2-MG), apolipoprotein A1 (Apo-A1), haptoglobin, gamma-glutamyl transferase (GGT), total bilirubin (TB) and hyaluronic acid (HA). The fibrotest score was computed after adjusting for age and gender. Predictive values and ROC curves were used to assess the accuracy of fibrotest and HA results. Results: For fibrotest, the observed area under curve for the discrimination between minimal or no fibrosis (F0-F1) and significant fibrosis (F2-F4) was 0.6736 for cutoff value 0.19 with sensitivity of 84.2% and specificity of 85.7%. For HA, the sensitivity was 89.5% and specificity was 85.7% and area under curve was 0.540 at the best cutoff value 71 mg/dL. Multi-use of both parameters, HA at 71 mg/dL with fibrotest score at 0.22 give a sensitivity 89.5%, specificity 100 and efficacy 92.3% (AUC 0.895). Conclusion: The use of both fibrotest score and HA could be as alternative to biopsy in most patients with chronic hepaitis C putting in consideration some limitations of the proposed markers in evaluating liver fibrosis.

Keywords: fibrotest, liver fibrosis, HCV RNA, biochemical markers

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Authors: K. R. Phaneesh, Anirudh Bhat, G. Mukherjee, K. T. Kashyap

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Extensive Monte Carlo Potts model simulations were performed on 2D square lattice to investigate the effects of simulated higher temperatures effects on grain growth kinetics. A range of simulation temperatures (KTs) were applied on a matrix of size 10002 with Q-state 64, dispersed with a wide range of second phase particles, ranging from 0.001 to 0.1, and then run to 100,000 Monte Carlo steps. The average grain size, the largest grain size and the grain growth exponent were evaluated for all particle fractions and simulated temperatures. After evaluating several growth parameters, the critical temperature for a square lattice, with eight nearest neighbors, was found to be KTs = 0.4.

Keywords: average grain size, critical temperature, grain growth exponent, Monte Carlo steps

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Authors: Osiris Jorge Parcero, Néstor Gandelman, Flavia Roldán, Josef Montag

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This paper uses cross-country unbalanced panel data of up to 146 countries over the period 1996 to 2015 to be the first study to identify potential determinants of a country’s relative research output in Economics versus Business. More generally, it is also one of the first studies comparing Economics and Business. The results show that better policy-related data availability, higher income inequality, and lower ethnic fractionalization relatively favor economics. The findings are robust to two alternative fixed effects specifications, three alternative definitions of economics and business, two alternative measures of research output (publications and citations), and the inclusion of meaningful control variables. To the best of our knowledge, our paper is also the first to demonstrate the importance of policy-related data as drivers of economic research. Our regressions show that the availability of this type of data is the single most important factor associated with the prevalence of economics over business as a research domain. Thus, our work has policy implications, as the availability of policy-related data is partially under policy control. Moreover, it has implications for students, professionals, universities, university departments, and research-funding agencies that face choices between profiles oriented toward economics and those oriented toward business. Finally, the conclusions show potential lines for further research.

Keywords: research output, publication performance, bibliometrics, economics, business, policy-related data

Procedia PDF Downloads 119

Authors: Nuray Gökçek Karaca

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This study aims to examine the application of occupational health and safety supervision in Turkey and EU countries in terms of legal regulations. The results of research reveal that occupational health and safety supervision in EU countries, whatever the understanding of welfare state, is effectively carried out and almost all legal regulations on this subject are consistent with the EU directives. On the other hand, there are serious problems in applications, not legal regulations, of occupational health and safety supervision in Turkey by the side of EU countries. Indeed, Turkey has modern regulations on occupational health and safety supervision whereas there are several problems such as ignoring prevention policy on occupational health and safety supervision, understanding of monotype inspector, problems resulting from this understanding and dispersed structure of occupational health and safety organizations in workplaces. As a result, Turkey needs to carry out effective supervision mechanisms.

Keywords: legal rules, occupational health and safety, inspection, supervision, legislation

Procedia PDF Downloads 767

Authors: S. Botman, D. Borchevkin, V. Petrov, E. Bogdanov, M. Patrushev, N. Shusharina

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In this paper, we report the development of the device for diagnostics of cardiovascular system state and associated automated workstation for large-scale medical measurement data collection and analysis. It was shown that optimal design for the monitoring device is wristband as it represents engineering trade-off between accuracy and usability. The monitoring device is based on the infrared reflective photoplethysmographic sensor, which allows collecting multiple physiological parameters, such as heart rate and pulsing wave characteristics. Developed device use BLE interface for medical and supplementary data transmission to the coupled mobile phone, which process it and send it to the doctor's automated workstation. Results of this experimental model approbation confirmed the applicability of the proposed approach.

Keywords: cardiovascular diseases, health monitoring systems, photoplethysmography, pulse wave, remote diagnostics

Procedia PDF Downloads 482

Authors: Hassan S. Hussein, Rania A. Abul Seoud, Amr M. Refaat

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Scientific researchers face in the analysis of very large data sets that is increasing noticeable rate in today’s and tomorrow’s technologies. Hadoop and Spark are types of software that developed frameworks. Hadoop framework is suitable for many Different hardware platforms. In this research, a scientific Linux cluster for Big Data analysis (SLBD) is presented. SLBD runs open source software with large computational capacity and high performance cluster infrastructure. SLBD composed of one cluster contains identical, commodity-grade computers interconnected via a small LAN. SLBD consists of a fast switch and Gigabit-Ethernet card which connect four (nodes). Cloudera Manager is used to configure and manage an Apache Hadoop stack. Hadoop is a framework allows storing and processing big data across the cluster by using MapReduce algorithm. MapReduce algorithm divides the task into smaller tasks which to be assigned to the network nodes. Algorithm then collects the results and form the final result dataset. SLBD clustering system allows fast and efficient processing of large amount of data resulting from different applications. SLBD also provides high performance, high throughput, high availability, expandability and cluster scalability.

Keywords: big data platforms, cloudera manager, Hadoop, MapReduce

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Authors: Caihong Sun, Xizi Zhang

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Rating prediction is an important problem for recommender systems. The task is to predict the rating for an item that a user would give. Most of the existing algorithms for the task ignore the effect of negative ratings rated by users on items, but the negative ratings have a significant impact on users’ purchasing decisions in practice. In this paper, we present a rating prediction algorithm based on factorization machines that consider the effect of negative ratings inspired by Loss Aversion theory. The aim of this paper is to develop a concave and a convex negative disgust function to evaluate the negative ratings respectively. Experiments are conducted on MovieLens dataset. The experimental results demonstrate the effectiveness of the proposed methods by comparing with other four the state-of-the-art approaches. The negative ratings showed much importance in the accuracy of ratings predictions.

Keywords: factorization machines, feature engineering, negative ratings, recommendation systems

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Authors: Tamar Makharadze, Anastasia Kitiashvili, Irine Zhvania, Tamar Abashidze

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After ratification of UN Convention on the Rights of Persons with Disabilities (UN CRPD) by the Parliament of Georgia in 2013, ensuring equal access to education and employment for people with disabilities has become one of the priorities of the government. The current research has analyzed the attitudes of people with disabilities, employers and society towards various challenges that employment of persons with disabilities faces in Georgia. The study has been carried out in the capital city and three towns in West and East Georgia. Both quantitative and qualitative research methods have been used. Employers’ attitudes have been studied by analyzing research data from six focus groups and 12 in-depth interviews. Views of persons with disabilities have been analyzed relied on data from eight focus groups and 14 in-depth interviews. The quantitative study covered 490 surveyed respondents from four cities in Georgia. The research was carried out with the employees of companies selected based on the Simple Random Sample; in each company, based on the size of the company 7–10 employees were surveyed. A survey was conducted using a specially developed structured questionnaire. Data analysis was carried out using SPSS (21.0). The research was carried out during June-August 2015. The research data shows that both qualitative and quantitative research participants view employment of persons with disabilities positively; however persons with severe intellectual disabilities and mental problems are viewed as less workable and desired at workplaces. The respondents support the idea of employment of persons with disabilities at an open labour market; at the same time idea of a development of sheltered workshops is also supported. The vast majority of research participants believe that employers should be rather encouraged to hire persons with disabilities than force them to do so. For employers it is important to have the state assistance in adjusting working place to the needs of employee with disabilities. Some tax benefits for employers having employees with disabilities also are seen as encouraging employment of persons with disabilities. Both employers and persons with disabilities believe that development of job coaching will help persons with disabilities to find and maintain a job at the open market. Majority of survey respondents think that the main reasons discouraging employment of persons with disabilities in Georgia are: poor socioeconomic background and high level of unemployment in the country, absence of related state programs and existed stigma towards persons with disabilities within the society. To conclude it can be said that both employers and persons with disabilities expect initiative from the government – development of the programs and services focusing on employment of persons with disabilities that will be rather encouraging and supporting than punishing and forcing. Relied on survey data it can be said that people have positive attitudes to see persons with disabilities at workplaces, educational institutions and public places. This creates a good background for extensive and consistent work towards social inclusion of persons with disabilities in Georgia.

Keywords: supported employment, job coaching, employment of persons with disabilities in Georgia, social inclusion

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Authors: M. Shukry

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According to the United Nations Declaration of Human Rights in 1948, every human being is entitled to rights in life that should be respected by others and protected by the state and community. Such rights are inherent regardless of colour, ethnicity, gender, religion or otherwise, and it is expected that all humans alike have the right to live without discrimination of any sort. However, that has not been the case with Aborigines in Australia. Over a long period of time, the governments of the State and the Territories and the Australian Commonwealth denied the Aboriginal and Indigenous inhabitants of the Torres Strait Islands such rights. Past Australian governments set policies and laws that enabled them to forcefully remove Indigenous children from their parents, which resulted in creating lost generations living the trauma of the loss of cultural identity, alienation and even their own selfhood. Intending to reduce that population of natives and their Aboriginal culture while, on the other hand, assimilate them into mainstream society, they gave themselves the right to remove them from their families with no hope of return. That practice has led to tragic consequences due to the trauma that has affected those children, an experience that is depicted by Jane Harrison in her play Stolen. The drama is the outcome of a six-year project on lost children and which was first performed in 1997 in Melbourne. Five actors only appear on the stage, playing the role of all the different characters, whether the main protagonists or the remaining cast, present or non-present ones as voices. The play outlines the life of five children who have been taken from their parents at an early age, entailing a disastrous negative impact that differs from one to the other. Unknown to each other, what connects between them is being put in a children’s home. The purpose of this paper is to analyse the play’s text in light of the 1948 Declaration of Human Rights, using it as a lens that reflects the atrocities practiced against the Aborigines. It highlights how such practices formed an outrageous violation of those natives’ rights as human beings. Harrison’s dramatic technique in conveying the children’s experiences is through a non-linear structure, fluctuating between past and present that are linked together within each of the five characters, reflecting their suffering and pain to create an emotional link between them and the audience. Her dramatic handling of the issue by fusing tragedy with humour as well as symbolism is a successful technique in revealing the traumatic memory of those children and their present life. The play has made a difference in commencing to address the problem of the right of all children to be with their families, which renders the real meaning of having a home and an identity as people.

Keywords: aboriginal, audience, Australia, children, culture, drama, home, human rights, identity, Indigenous, Jane Harrison, memory, scenic effects, setting, stage, stage directions, Stolen, trauma

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Authors: Y. Galerkin, K. Soldatova, A. Drozdov

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The 6th version of Universal modeling method for centrifugal compressor stage calculation is described. Identification of the new mathematical model was made. As a result of identification the uniform set of empirical coefficients is received. The efficiency definition error is 0,86 % at a design point. The efficiency definition error at five flow rate points (except a point of the maximum flow rate) is 1,22 %. Several variants of the stage with 3D impellers designed by 6th version program and quasi three-dimensional calculation programs were compared by their gas dynamic performances CFD (NUMECA FINE TURBO). Performance comparison demonstrated general principles of design validity and leads to some design recommendations.

Keywords: compressor design, loss model, performance prediction, test data, model stages, flow rate coefficient, work coefficient

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Authors: Hadiseh Hosamirudsari, Farhad Afsarikordehmahin, Pooria Sekhavatfar

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Concomitant cortical blindness and deafness that follow varicella zoster virus (VZV) infection is rare. We describe a case of ophthalmic zoster that caused cortical blindness and deafness after central nervous system (CNS) involvement. A 42-year old, HIV infected woman has developed progressive blurry vision and deafness, 4 weeks after ophthalmic zoster. A physical examination and positive VZV polymerase chain reaction (PCR) of cerebrospinal fluid (CSF) suggested VZV encephalitis. Complication of VZV encephalitis is considered as the cause of blindness and deafness. In neurological deficit patient especially with a history of herpes zoster, VZV infection should be regarded as the responsible agent in inflammatory disorders of nervous system. The immunocompromised state of patient (including HIV) is as important an agent as VZV infection in developing the disease.

Keywords: blindness, deafness, hiv, VZV encephalitis

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Authors: Esther Acha, Jose Cambra, De Chen

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Hydrogen is considered an important energy vector for the 21st century. Nowadays there are some difficulties for hydrogen economy implantation, and one of them is the high purity required for hydrogen. This energy vector is still being mainly produced from fuels, from wich hydrogen is produced as a component of a mixture containing other gases, such as CO, CO2 and H2O. A forthcoming sustainable pathway for hydrogen is steam-reforming of bio-oils derived from biomass, e.g. via fast pyrolysis. Bio-oils are a mixture of acids, alcohols, aldehydes, esters, ketones, sugars phenols, guaiacols, syringols, furans, multi-functional compounds and also up to a 30 wt% of water. The sorption enhanced steam reforming (SESR) process is attracting a great deal of attention due to the fact that it combines both hydrogen production and CO2 separation. In the SESR process, carbon dioxide is captured by an in situ sorbent, which shifts the reversible reforming and water gas shift reactions to the product side, beyond their conventional thermodynamic limits, giving rise to a higher hydrogen production and lower cost. The hydrogen containing mixture has been obtained from the SESR of bio-oil type compounds. Different types of catalysts have been tested. All of them contain Ni at around a 30 wt %. Two samples have been prepared with the wet impregnation technique over conventional (gamma alumina) and non-conventional (olivine) supports. And a third catalysts has been prepared over a hydrotalcite-like material (HT). The employed sorbent is a commercial dolomite. The activity tests were performed in a bench-scale plant (PID Eng&Tech), using a stainless steel fixed bed reactor. The catalysts were reduced in situ in the reactor, before the activity tests. The effluent stream was cooled down, thus condensed liquid was collected and weighed, and the gas phase was analysed online by a microGC. The hydrogen yield, and process behavior was analysed without the sorbent (the traditional SR where a second purification step will be needed but that operates in steady state) and the SESR (where the purification step could be avoided but that operates in batch state). The influence of the support type and preparation method will be observed in the produced hydrogen yield. Additionally, the stability of the catalysts is critical, due to the fact that in SESR process sorption-desorption steps are required. The produced hydrogen yield and hydrogen purity has to be high and also stable, even after several sorption-desorption cycles. The prepared catalysts were characterized employing different techniques to determine the physicochemical properties of the fresh-reduced and used (after the activity tests) materials. The characterization results, together with the activity results show the influence of the catalysts preparation method, calcination temperature, or can even explain the observed yield and conversion.

Keywords: CO2 sorbent, enhanced steam reforming, hydrogen

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Authors: Satoshi Furukawa, Satomu Morita, Katsuji Nishi, Masahito Hitosugi

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We experience the autopsy cases that the deceased was alive in emergency room on arrival. Bleeding is the leading cause of preventable death after injury. This retrospective study aimed to characterize opportunities for performance improvement identified in patients who died from traffic trauma and were considered by the quality improvement of education system. The Japan Advanced Trauma Evaluation and Care (JATEC) education program was introduced in 2002. We focused the abdominal traffic trauma injury. An autopsy-based cross-sectional study conducted. A purposive sampling technique was applied to select the study sample of 41 post-mortems of road traffic accident between April 1999 and March 2014 subjected to medico-legal autopsy at the department of Forensic Medicine, Shiga University of Medical Science. 16 patients (39.0%) were abdominal trauma injury. The mean period of survival after meet with accident was 13.5 hours, compared abdominal trauma death was 27.4 hours longer. In road traffic accidents, the most injured abdominal organs were liver followed by mesentery. We thought delayed treatment was associated with immediate diagnostic imaging, and so expected to expand trauma management examination.

Keywords: abdominal traffic trauma, preventable death, autopsy, emergency medicine

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Authors: Fahimeh Helali Soltanahmadi, Alireza Nourabdi

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To investigate the effects of seed pretreatment on drought tolerance, an experimental Marigold (Calendula officinalis L) was tested in 2017-2018. A germination experiment was performed in the laboratory of Urmia University. The experiment was performed as a factorial experiment in a completely randomized design with three replications. The experimental treatments were dry levels of polyethylene glycol in four levels (control, -3, -6 and -9 bar) and treatments of Humic acid (72 mg / l), salicylic acid (2000 μmol) and ascorbic acid (200 ppm), and control were performed. The results of the germination experiment showed that with increasing drought levels caused by polyethylene glycol, germination indices were significantly reduced, so that the highest value obtained from the measured traits was observed in normal irrigation and in priming treatments, and the lowest amount of these traits was observed at the -9 bar drought level due to polyethylene glycol in the control treatment. The results of this study showed an increase in drought tolerance and improved Marigold germination under stress by applying seed priming with salicylic acid, which is recommended in sustainable and organic agriculture.

Keywords: Marigold, organic matter, seed pretreatment, drought stress, allometric coefficient

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Authors: Miroslav Mrlik, Marketa Ilcikova, Martin Cvek, Josef Osicka, Michal Sedlacik, Vladimir Pavlinek, Jaroslav Mosnacek

Abstract:

Magnetorheological elastomers (MREs) are a unique type of materials consisting of two components, magnetic filler, and elastomeric matrix. Their properties can be tailored upon application of an external magnetic field strength. In this case, the change of the viscoelastic properties (viscoelastic moduli, complex viscosity) are influenced by two crucial factors. The first one is magnetic performance of the particles and the second one is off-state stiffness of the elastomeric matrix. The former factor strongly depends on the intended applications; however general rule is that higher magnetic performance of the particles provides higher MR performance of the MRE. Since magnetic particles possess low stability properties against temperature and acidic environment, several methods how to improve these drawbacks have been developed. In the most cases, the preparation of the core-shell structures was employed as a suitable method for preservation of the magnetic particles against thermal and chemical oxidations. However, if the shell material is not single-layer substance, but polymer material, the magnetic performance is significantly suppressed, due to the in situ polymerization technique, when it is very difficult to control the polymerization rate and the polymer shell is too thick. The second factor is the off-state stiffness of the elastomeric matrix. Since the MR effectivity is calculated as the relative value of the elastic modulus upon magnetic field application divided by elastic modulus in the absence of the external field, also the tuneability of the cross-linking reaction is highly desired. Therefore, this study is focused on the controllable modification of magnetic particles using a novel monomeric system based on 2-(1H-pyrrol-1-yl)ethyl methacrylate. In this case, the short polymer chains of different chain lengths and low polydispersity index will be prepared, and thus tailorable stability properties can be achieved. Since the relatively thin polymer chains will be grafted on the surface of magnetic particles, their magnetic performance will be affected only slightly. Furthermore, also the cross-linking density will be affected, due to the presence of the short polymer chains. From the application point of view, such MREs can be utilized for, magneto-resistors, piezoresistors or pressure sensors especially, when the conducting shell on the magnetic particles will be created. Therefore, the selection of the pyrrole-based monomer is very crucial and controllably thin layer of conducting polymer can be prepared. Finally, such composite particle consisting of magnetic core and conducting shell dispersed in elastomeric matrix can find also the utilization in shielding application of electromagnetic waves.

Keywords: atom transfer radical polymerization, core-shell, particle modification, electromagnetic waves shielding

Procedia PDF Downloads 198

Authors: M. Umar Hafeez, Furqan Khursheed Hashmi, Nadeem Irfan Bukhari, Shahzad Ali, Muzammil Ali

Abstract:

The trend of self-medication is increasing due to various factors and is associated with a large number of complications. A cross-sectional study was aimed to investigate self-medication trend in an urban community and its correlates such as level of education, gender and behavior of using psychoactive medicines. A validated questionnaire was used to collect the data from different locations of Lahore, provincial capital of Punjab, Pakistan. The trend of self-medication was noted in reference to difference in educational level and in gender. This study showed that total 110 respondents, all literate,were found to be self-medicating, and their educational status was as 73.13% primary, 63.15% secondary, 61.12% higher secondary and 62.15% university going. In this sample 74.99% were males and 48.00%were females. Twenty nine (26.36%) of the total sample were found to be using psychoactive agents without consulting the physician. The trend of self-medication was 10% higher in individuals having primary level education, whereas there was not much difference of self-medication trend in other levels of education. The main reasons involved in self-medication trend were socio-economic status, medicine accessibility, religious and cultural beliefs, lack of awareness about risks associated with medicine, non-prescription sale of medicines and previous medication experience. The trend of self-medication of psychotropic agents is quite significant.

Keywords: self-medication, educated community, psychotropic drugs, education levels

Procedia PDF Downloads 381

Authors: F. Zouai, F. Z. Benabid, S. Bouhelal, D. Benachoura

Abstract:

A (PET)/clay nano composites has been successfully performed in one step by reactive melt extrusion. The PEN was first mixed in the melt state with different amounts of functionalized clay. It was observed that the composition PET/4 wt% clay showed total exfoliation. These completely exfoliated composition called nPET, was used to prepare new nPET nano composites in the same mixing batch. The nPEN was compared to neat PET. The nanocomposites were characterized by different techniques: differential scanning calorimetry (DSC) and wide-angle X-ray scattering (WAXS). The micro and nanostructure/properties relationships were investigated. From the different WAXS patterns, it is seen that all samples are amorphous phase. In addition, nPET blends present lower Tc values and higher Tm values than the corresponding neat PET. The present study allowed establishing good correlations between the different measured properties.

Keywords: PET, montmorillonite, nanocomposites, exfoliation, reactive melt-mixing

Procedia PDF Downloads 393

Authors: Luís Farinha, João J. Ferreira

Abstract:

Nowadays innovation represents a challenge crucial to remaining globally competitive. This study seeks to develop a conceptual model aimed at measuring the dynamic interactions of the triple/quadruple helix, balancing innovation and entrepreneurship initiatives as pillars of regional competitiveness – the Regional Helix Scoreboard (RHS). To this aim, different strands of literature are identified according to their focus on specific regional competitiveness governance mechanisms. We put forward an overview of the state-of-the-art of research and is duly assessed in order to develop and propose a framework of analysis that enables an integrated approach in the context of collaborative dynamics. We conclude by presenting the RHS for the study of regional competitiveness dynamics, which integrates and associates different backgrounds and identifies a number of key performance indicators for research challenges.

Keywords: entrepreneurship, KPIs, innovation, performance measurement, regional competitiveness, regional helix scoreboard

Procedia PDF Downloads 316