Search results for: African Standby Force

Authors: Olaifa Temitope Abimbola

Abstract:

The spate of the occurrence of Ethnic Conflict in Nigeria and indeed Africa is sporadic and to say the least alarming. To scholars of Ethnic Conflict in Africa, it has defied all logical approaches to its resolution. Based on this fact international organisations have begun to look for alternative means of approaching these conflicts. Not a few have agreed that wars are better and cheaper prevented than resolved or transformed. In the light of this, this paper had set out to look at the concept of Preventive Diplomacy, Ethnic Conflict, Women and the role they play in mitigating conflict by researching into activities of women in pre and post-conflict situations in selected African conflict and has been able to establish the peculiar capacity of women in dousing tension both at domestic and communal levels.

Keywords: preventive diplomacy, gender, peacebuilding, low

Procedia PDF Downloads 588

Authors: Kerryn Krige, Kerrin Myers

Abstract:

Social entrepreneurship offers the opportunity to simultaneously address both social and economic inequality in South Africa. Its appeal across racial groups, its attractiveness to young people, its applicability in rural and peri-urban markets, and its acceleration in middle income, large-business economies suits the South African context. However, the potential to deliver much-needed developmental benefits has not been realised because the social entrepreneurship debate lacks evidence as to who social entrepreneurs are, their goals and operations and the socio-economic results they achieve. As a result, policy development has been stunted, and legislative barriers and red tape remain. Social entrepreneurs are isolated from the mainstream economy, and struggle to access funding because of limitations in legislative and organisational structures. The objective of the study is to strengthen the ecosystem for social entrepreneurship in South Africa by producing robust, policy-rich information from and about social enterprises currently in operation across the country. The study employs a quantitative survey methodology, using online and telephonic data collection methods. A purposive sample of 1000 social enterprises was included in the first large-scale study of social entrepreneurship in South Africa. The results offer deep insight into the characteristics of social enterprises; the activities they undertake and the markets they serve; their modes of operation and funding sources as well as key challenges and support systems. The results contribute towards developing a model of social enterprise in the African context.

Keywords: social enterprise, key characteristics, challenges and enablers, towards an African model

Procedia PDF Downloads 310

Authors: Jobin Varghese, V. M. Akhil, P. K. Rajendrakumar, K. S. Sivanandan

Abstract:

The major contributor to the human locomotion is the knee flexion and extension. During heel strike, a huge amount of energy is transmitted through the leg towards knee joint, which in fact is damped at heel and leg muscles. During high shocks, although it is damped to a certain extent, the balance force transmits towards knee joint which could damage the knee. Due to the vital function of the knee joint, it should be protected against damage due to additional load acting on it. This work concentrates on the development of spring mass damper system which exactly replicates the stiffness at the heel and muscles and the objective function is optimized to minimize the force acting at the knee joint. Further, the data collected using force plate are put into the model to verify its integrity and are found to be in good agreement.

Keywords: spring, mass, damper, knee joint

Procedia PDF Downloads 272

Authors: Eung Ryeol Seo, Hee Tae Lim, Eunsuk Bang, Soon Cheol Kweon, Jeoung-Kyo Jeoung, Ji-Hoon Choic

Abstract:

The object of this study is to investigate the effect of pulsator on washing performance quantitatively for front-loading washer. The front-loading washer with pulsator shows washing performance improvement of 18% and the particle-based body simulation technique has been applied to figure out the relation between washing performance and mechanical forces exerted on textile during washing process. As a result, the mechanical forces, such as collision force and strain force, acting on the textile have turned out to be about twice numerically. The washing performance improvement due to additional pulsate system has been utilized for customers to save 50% of washing time.

Keywords: front-loading washer, mechanical force, fabric movement, pulsator, time-saving

Procedia PDF Downloads 262

Authors: Ekrem Erdem, Can Tansel Tugcu

Abstract:

Improved resource efficiency of production is a key requirement for sustainable growth, worldwide. In this regards, by considering the energy and tourism as the extra inputs to the classical Coub-Douglas production function, this study aims at investigating the efficiency changes in the North African countries. To this end, the study uses panel data for the period 1995-2010 and adopts the Malmquist index based on the data envelopment analysis. Results show that tourism increases technical and scale efficiencies, while it decreases technological and total factor productivity changes. On the other hand, when the production function is augmented by the energy input, technical efficiency change decreases, while the technological change, scale efficiency change and total factor productivity change increase. Thus, in order to satisfy the needs for sustainable growth, North African governments should take some measures for increasing the contribution that the tourism makes to economic growth and some others for efficient use of resources in the energy sector.

Keywords: data envelopment analysis, economic efficiency, North African countries, sustainable growth

Procedia PDF Downloads 346

Authors: Adheesh Budree, Olaf Jacob, Louis CH Fourie, James Njenga, Gabriel D Hoffman

Abstract:

Business Intelligence (BI) is implemented by organisations for many reasons and chief among these is improved data support, decision support and savings. The main purpose of this study is to determine BI requirements and availability within South African organisations. The study addresses the following areas as identified as part of a literature review; assessing BI practices in businesses over a range of industries, sectors and managerial functions, determining the functionality of BI (technologies, architecture and methods). It was found that the overall satisfaction with BI in larger organisations is low due to lack of ability to meet user requirements.

Keywords: business intelligence, business value, data management, South Africa

Procedia PDF Downloads 578

Authors: Anne Kubai

Abstract:

Since the Lisbon Summit in 2007, discussion and dialogue on ways of enhancing collaboration between Africa and the EU on the issues of migration, mobility and employment has intensified. The Africa-EU Partnership on migration, mobility and employment aims to provide far-reaching responses on migration and employment challenges; and facilitate mobility of people in Africa and the EU. However, since the outcomes of the proposed policies depend on the political interests and institutional capacities of both the EU and African states that are involved, the results have so far been uncoordinated and scattered. Also, many European countries have eased their entry regulations with regard to highly skilled migrants, and there is need to explore the implications of such changes. Therefore, this contribution will address the following questions: How has the progression of migration and border management in the Nordic countries, particularly Sweden, affected the flow and mobility of highly skilled migrants from Africa? What is the possible impact of the changes in receiving countries (such as introduction of tuition fees and more stringent admission regulations for foreign students in Sweden) on skilled migration and mobility? How can highly skilled immigrants be a source of research knowledge between international and local institutions and researchers both in sending and receiving countries?

Keywords: academic mobility, skilled, African, knowledge, research, migrants, Sweden

Procedia PDF Downloads 322

Authors: A. S. Lourens, B. Du Plooy

Abstract:

Across the world, initiatives have been introduced to encourage women to enter into and remain in engineering fields. However, research has shown that many women leave engineering or suffer a loss of self-esteem and self-confidence compared to their male counterparts. To address this problem, a South African comprehensive university developed a self-leadership intervention pilot study in 2013, aimed at improving the self-efficacy of its female engineering students and increasing retention rates. This paper is a qualitative, descriptive and interpretive study of the rationale and operational aspects of the Women in Engineering Leadership Association’s (WELA) self-leadership workshop. The objectives of this paper are to provide a framework for the design of a self-leadership workshop and to provide insight into the process of developing such a workshop specifically for women engineering students at a South African university. Finally, the paper proposes an evaluation process for the pilot workshop, which also provides a framework to improve future workshops. It is anticipated that the self-leadership development framework will be applicable to other higher education institutions wishing to improve women engineering student’s feelings of self-efficacy and therefore retention rates of women in engineering.

Keywords: self-leadership, women in engineering, co-curricular interventions, self-efficacy

Procedia PDF Downloads 399

Authors: Balogun R. Ayodeji, Adefisan E. Adesanya, Adeyewa Z. Debo, E. C. Okogbue

Abstract:

Deep convective systems during active periods of the West African monsoon season have not been properly investigated over better temporal and spatial resolution in West Africa. Deep convective systems are investigated over seven climatic zones of the West African sub-region, which are; west-coast rainforest, dry rainforest, Nigeria-Cameroon rainforest, Nigeria savannah, Central African and South Sudan (CASS) Savannah, Sudano-Sahel, and Sahel, using data from Tropical Rainfall Measurement Mission (TRMM) Precipitation Feature (PF) database. The vertical structure of the convective systems indicated by the presence of at least one 40 dBZ and reaching (attaining) at least 1km in the atmosphere showed strong core (highest frequency (%)) of reflectivity values around 2 km which is below the freezing level (4-5km) for all the zones. Echoes are detected above the 15km altitude much more frequently in the rainforest and Savannah zones than the Sudano and Sahel zones during active periods in March-May (MAM), whereas during active periods in June-September (JJAS) the savannahs, Sudano and Sahel zones convections tend to reach higher altitude more frequently than the rainforest zones. The percentage frequencies of deep convection indicated that the occurrences of the systems are within the range of 2.3-2.8% during both March-May (MAM) and June-September (JJAS) active periods in the rainforest and savannah zones. On the contrary, the percentage frequencies were found to be less than 2% in the Sudano and Sahel zones, except during the active-JJAS period in the Sudano zone.

Keywords: active periods, convective system, frequency, reflectivity

Procedia PDF Downloads 152

Authors: Simont Toussi

Abstract:

Cameroon and the Central African Republic arebound by the provisions of many regional and international charters, which condemn the manipulation of information, obstacles to access reliable information, or the limitation of freedoms of expression and opinion. These two countries also have constitutional guarantees for free speech and access to true and liable information. However, they are yet to define specific policies and regulations for access to information, disinformation, or misinformation. Yet, certain countries’ laws and regulations related to information and communication technologies, to criminal procedures, to terrorism, or intelligence services contain provisions that rather hider human rights by condemning false information. Like many other African countries, Cameroon and the Central African Republic face a profound democratic regression, and governments use multiple methods to stifle online discourse and digital rights. Despite the increased uptake of digital tools for political participation, there is a lack of interactivity and adoption of these tools. This enables a scarcity of information and creates room for the spreading of disinformation in the public space, hamperingdemocracy and the respect for human rights. This research aims to analyse the adequacy of stakeholders’ responses to disinformation in Cameroon and the Central African Republic in periods of political contestation, such as elections and anti-government protests, to highlight the nature, perpetrators, strategies, and channels of disinformation, as well as its effects on democratic actors, including civil society, bloggers, government critics, activists, and other human rights defenders. The study follows a qualitative method with literature review, content analysis, andkey informant’sinterviews with stakeholders’ representatives, emphasized crowdsourcing as a data and information collecting method in the two countries.

Keywords: disinformation, democracy, political manipulation, social media, media, fake news, central Africa, cameroon, misinformation, free speech

Procedia PDF Downloads 109

Authors: Mahesh K. Chudasama, Harit K. Raval

Abstract:

3-roller conical bending process is widely used in the industries for manufacturing of conical sections and shells. It involves static as well dynamic bending stages. Analytical models for prediction of bending force during static as well as dynamic bending stage are available in the literature. In this paper, bending forces required for static bending stage and dynamic bending stages have been compared using the analytical models. It is concluded that force required for dynamic bending is very less as compared to the bending force required during the static bending stage.

Keywords: analytical modeling, cone frustum, dynamic bending, static bending

Procedia PDF Downloads 308

Authors: Hyeong-Gyu Park, Hak-Gon Noh, Beom-Soo Kang, Jeong Kim

Abstract:

Electromagnetic forming (EMF) process is one of a high-speed forming process, which uses an electromagnetic body (Lorentz) force to deform work-piece. Advantages of EMF are summarized as improvement of formability, reduction in wrinkling, non-contact forming. In this study, the spiral coil is considered to evaluate formability in terms of pressure distribution of the forming process. It also is represented forming results of numerical analysis using ANSYS code. In the numerical simulation, RLC circuit coupled with spiral coil was made to consider the design parameters such as system input current and electromagnetic force. The simulation results show that even though input peak currents level are same level in each case, forming condition is certainly different because of frequency of input current and magnitude of current density and magnetic flux density. Finally, the simulation results appear that electromagnetic forming force apparently affected by input current frequency which determines magnitude of current density and magnetic flux density.

Keywords: electromagnetic forming, high-speed forming, RLC circuit, Lorentz force

Procedia PDF Downloads 456

Authors: A. I. O. Zaid

Abstract:

Deep drawing is considered to be the most widely used sheet metal forming processes among the particularly in automobile and aircraft industries. It is widely used for manufacturing a large number of the body and spare parts. In its simplest form it may be defined as a secondary forming process by which a sheet metal is formed into a cylinder or alike by subjecting the sheet to compressive force through a punch with a flat end of the same geometry as the required shape of the cylinder end while it is held by a blank holder which hinders its movement but does not stop it. The punch and die profile radii play In this paper, the effects of punch and die profile radii on the autographic record, the minimum thickness strain location where the cracks normally start and cause the fracture, the maximum deep drawing force and the total consumed work in the drawing flat ended cylindrical brass cups are investigated. Five punches and five dies each having different profile radii were manufactured for this investigation. Furthermore, their effect on the quality of the drawn cups is also presented and discussed. It was found that the die profile radius has more effect on the maximum drawing force and the total consumed work than the punch profile radius.

Keywords: punch and die profile radii, deep drawing process, maximum drawing force, total consumed work, quality of produced parts, flat ended cylindrical brass cups

Procedia PDF Downloads 339

Authors: Tejinder Singh

Abstract:

This paper describes a new more efficient Hydraulic System which uses lesser work to produce more output. Conventional Hydraulic System like Hydraulic Lifts and Rams use lots of water to be pumped to produce output. TejHydroLift will do the equal amount of force with lesser input of water. The paper will show that force applied can be increased manifold without requiring to move smaller force by more distance which used to be required in Conventional Hydraulic Lifts. The paper describes one of the configurations of TejHydroLift System called “Slim Antenna TejHydroLift Configuration”. The TejHydroLift uses lesser water and hence demands lesser work to be performed to move the same load.

Keywords: alternate, hydraulic system, efficient, TejHydroLift

Procedia PDF Downloads 260

Authors: Leslie Nobler

Abstract:

African fabrics based specifically on the Dutch Wax Print, or Ankara, popularized during Africa's colonial era, have had an enormous impact on western fashion (especially in the US and UK), in the last half-decade. The trend has had an effect on the world of visual arts as well, which circuitously, also heavily impacts fashion design. In fashion, and notably in celebrity apparel choices, this is in part due to ‘identity’ and taking pride in one's African roots; in the visual arts, artists such as Yinka Shonibare and Njideka Akunyili Crosby are making statements about identity politics, colonialism up through post-colonialism, and racism. The ‘global village’ brought on by the internet has driven this proliferation, as have improvements in the printing technology with which the Ankara print is made, combining wax-resist with roller printing. The newest patterns can now be designed authentically in western African and easily sent electronically to Europe for printing. Examples of Ankara's new reach across the Atlantic abound. They have taken several paths, which the paper will detail. Briefly, the first is its greater utilization in the fashion world, from authentic textile shops in African American neighborhoods to copied (knocked-off) low-end reproductions in discount chains. Secondly, we are seeing far more uses of these textiles/patterns in important works of fine arts from major museums, in Philadelphia to Palm Beach to the Mass MOCA (in the US), all the way to the Israel Museum in Jerusalem, and everywhere in between. And lastly, but quite significantly, we see this trend throughout social media thanks to Instagram, Pinterest and celebrity photos –even at the recent royal wedding. What shall sustain this major new design direction is that Ankara changes with and adapts to the times. Some of it is now printed in West Africa, often in the Nigeria area. And some may be designed in Europe or even at knock-off apparel studios in NY or Asia. But it stays utterly relevant because the motifs are based on objects and scenes in everyday life. In my design studio and university design classes, this idea is first and foremost, from our big spiritual eye motifs to drawings of our art supplies to the ‘politically-loaded’ chain patterns. This first-hand creativity experience becomes part of the research of this paper, along with historic and contemporary sources of inquiry, both through a literature/image search and anecdotal experience into what is behind this exciting and surprising trend.

Keywords: African wax print, Ankara, identity (politics), textile design, surface design

Procedia PDF Downloads 135

Authors: Madhu Jain, Rakesh Kumar Meena

Abstract:

This paper investigates a finite M/G/1 fault tolerant multi-component machining system. The system incorporates the features such as standby support, threshold recovery and imperfect coverage make the study closer to real time systems. The performance prediction of M/G/1 fault tolerant system is carried out using recursive approach by treating remaining service time as a supplementary variable. The numerical results are presented to illustrate the computational tractability of analytical results by taking three different service time distributions viz. exponential, 3-stage Erlang and deterministic. Moreover, the cost function is constructed to determine the optimal choice of system descriptors to upgrading the system.

Keywords: fault tolerant, machine repair, threshold recovery policy, imperfect coverage, supplementary variable technique

Procedia PDF Downloads 292

Authors: A. Asambe

Abstract:

A study was conducted to determine the level of compliance with sanitary measures in piggeries, and awareness and risk factors of African swine fever in Benue State, Nigeria. Questionnaires were distributed to 74 respondents consisting of piggery owners and attendants in different piggeries across 12 LGAs to collect data for this study. Sanitary measures in piggeries were observed to be generally very poor, though respondents admitted being aware of ASF. Piggeries located within a 1 km radius of a slaughter slab (OR=9.2, 95% CI - 3.0-28.8), piggeries near refuse dump sites (OR=3.0, 95% CI - 1.0-9.5) and piggeries where farm workers wear their work clothes outside of the piggery premises (OR=0.2, 95% CI - 0.1-0.7) showed higher chances of ASFV infection and were significantly associated (p < 0.0001), (p < 0.05) and (p < 0.01), and were identified as potential risk factors. The study concluded that pigs in Benue State are still at risk of an ASF outbreak. Proper sanitary and hygienic practices is advocated and emphasized in piggeries, while routine surveillance for ASFV antibodies in pigs in Benue State is strongly recommended to provide a reliable reference data base to plan for the prevention of any devastating ASF outbreak.

Keywords: African swine fever, awareness, piggery, risk factors, sanitary measures

Procedia PDF Downloads 177

Authors: Dagnew Dessie Mengie

Abstract:

The purpose of this study was to investigate German tourists' demand for Ethiopian tourism destinations. The author has made every effort to identify the differences in the preferences of German visitors’ demand in Ethiopia comparing with Egypt, Kenya, Tanzania, and South African tourism sectors if they are invited to visit at the same time. However, the demand for international tourism for Ethiopia currently lags behind these African countries. Therefore, to offer demand-driven tourism products, the Ethiopian government and tour and travel operators need to understand the important factors that affect international tourists’ decision to visit Ethiopian tourist destinations. The aim of this study was to analyze German Tourists’ Demand for Ethiopian destinations. The researcher aimed to identify the demand for German tourists’ preference for Ethiopian tourist destinations compared to the above-mentioned African countries. For collecting and analysing data for this study, both quantitative and qualitative methods of research are being used in this study. The most significant data are collected by using the primary data collection method i.e. survey and interviews which are the most and large number of potential responses and feedback from nine German active tourists,12 Ethiopian tourism officials, four African embassies, and four well functioning private tour companies and secondary data collected from books, journals, previous research and electronic websites. Based on the data analysis of the information gathered from interviews and questionnaires, the study disclosed that the majority of German tourists do have not that high demand for Ethiopian Tourist destinations due to the following reasons: (1) Many Germans are fascinated by adventures and safari and simply want to lie on the beach and relax. These interests have leaded them to look for other African countries which have these accesses. (2) Uncomfortable infrastructure and transport problems are attributed to the decreasing number of German tourists in the country. (3) Inadequate marketing operation of the Ethiopian Tourism Authority and its delegates in advertising and clarifying the above irregularities which are raised by the tourists.

Keywords: environmental benefits of tourism, social benefits of tourism, economic benefits of tourism, political factors on tourism

Procedia PDF Downloads 42

Authors: B. Varaprasad, C. Srinivasa Rao

Abstract:

Hard turning has been explored as an alternative to the conventional one used for manufacture of Parts using tool steels. In the present study, the effects of cutting speed, feed rate and Depth of Cut (DOC) on cutting forces, specific cutting force, power and surface roughness in the hard turning are experimentally investigated. Experiments are carried out using mixed ceramic(Al2O3+TiC) cutting tool of corner radius 0.8mm, in turning operations on AISI H13 tool steel, heat treated to a hardness of 62 HRC. Based on Design of Experiments (DOE), a total of 20 tests are carried out. The range of each one of the three parameters is set at three different levels, viz, low, medium and high. The validity of the model is checked by Analysis of variance (ANOVA). Predicted models are derived from regression analysis. Comparison of experimental and predicted values of specific cutting force, power and surface roughness shows that good agreement has been achieved between them. Therefore, the developed model may be recommended to be used for predicting specific cutting force, power and surface roughness in hard turning of tool steel that is AISI H13 steel.

Keywords: hard turning, specific cutting force, power, surface roughness, AISI H13, mixed ceramic

Procedia PDF Downloads 700

Authors: Zhao Hong

Abstract:

When international students study Chinese as a foreign or second language, it is important for them to form constructive viewpoints and possess an open mindset on Chinese culture. This helps them to make faster progress in their language acquisition. Observations from African students at Liaoning Institute of Science and Technology show that by integrating video-focused social networking apps such as Tiktok (“Douyin”) on a controlled basis, students raise their interest not only in making an effort in learning the Chinese language, but also in the understanding of the Chinese culture. During the last twelve months, our research group explored a teaching model using selected contents in certain classroom settings, including virtual classrooms during lockdown periods due to the COVID-19 pandemic. Using interviews, a survey was conducted on international students from African countries at the Liaoning Institute of Science and Technology in Chinese language courses. Based on the results, a teaching model was built for Chinese language acquisition by entering the "mobile Chinese culture".

Keywords: Chinese as a foreign language, cultural education, social networking apps, teaching model

Procedia PDF Downloads 74

Authors: Bronwyn Bell, Lizelle Brink

Abstract:

Workplaces of today are populated by employees from different generations; emerging adults being the most recent demographic group entering the workplace. These individuals form part of Generation Y and are between the ages of 18 to 25. Emerging adults bring unique and different characteristics to the workplace. These individuals also differ from other generations with regards to their employment desires and ways of working. Age-stereotypes of emerging adults is, therefore, a common occurrence within workplaces. The general objective of the study was therefore to explore age-related stereotypes experienced regarding emerging adults within the South African work context and to determine the influences thereof. A qualitative research design from the social constructivism paradigm was employed in order to reach the objectives of this research study. A phenomenological approach using a combination of purposive and snowball sampling was employed within this study. A sample of 25 employees (N = 25) from various South African organisations were interviewed for the purpose of this study and formed part of three generations namely Generation Y, Generation X and Baby Boomers. In order to analyse the collected data, the steps of thematic analysis were used. The main findings of this study indicated that emerging adults experience various positive and negative stereotypes within the workplace. Results further indicated that these stereotypes influence emerging adults in a behavioural, cognitive and emotional manner. These stereotypes also influence the way emerging adults are treated by older employees within the workplace. Recommendations based on the results of this study were made for future research and practice. This study creates awareness within organisations regarding age-stereotypes of emerging adults. By being aware, employees can manage the influences thereof within the workplace.

Keywords: age-stereotypes, baby boomers, emerging adults, generation x, generation y, South African work environment, stereotypes

Procedia PDF Downloads 294

Authors: A. S. Lourens, B. Du Plooy

Abstract:

Across the world, initiatives have been introduced to encourage women to enter into and remain in engineering fields. However, research has shown that many women leave engineering or suffer a loss of self-esteem and self-confidence compared to their male counterparts. To address this problem, a South African comprehensive university developed a self-leadership intervention pilot study in 2013, aimed at improving the self-efficacy of its female engineering students and increasing retention rates. This paper is a qualitative, descriptive, and interpretive study of the rationale and operational aspects of the Women in Engineering Leadership Association’s (WELA) self-leadership workshop. The objectives of this paper are to provide a framework for the design of a self-leadership workshop and to provide insight into the process of developing such a workshop specifically for women engineering students at a South African university. Finally, the paper proposes an evaluation process for the pilot workshop, which also provides a framework to improve future workshops. It is anticipated that the self-leadership development framework will be applicable to other higher education institutions wishing to improve women engineering student’s feelings of self-efficacy and therefore retention rates of women in engineering.

Keywords: co-curricular interventions, self-efficacy, self-leadership, women in engineering

Procedia PDF Downloads 450

Authors: Lawrence Akande

Abstract:

Despite the efforts of African countries' governments and the foreign countries' governments, there are cautions between the people of Africa and the people of other countries. The cautions are based on the ideology of misconception, which comes from the narratives about Africa and African people and narratives about other people also. The film is a medium of educating people about people from foreign countries they have never been to. Negative or misconceived narratives about a people will affect the relations between the peoples, despite the efforts of the government. Using pop-culture medium of film as a diplomatic tool will promote mutual understanding and respect.

Keywords: film diplomacy, international relations, narratives, Nollywood, partnership

Procedia PDF Downloads 205

Authors: Ersin Bozkurt, Şükran Erdoğan

Abstract:

The purpose of the study is to explore how pre-service teachers perceive buoyancy force effecting an object in a liquid and identify their misconceptions. Pre-service teachers were interviewed to reveal their understandings of an object's floating, suspending and sinking in a liquid. In addition, they were asked about how an object -given its features- moved when it is provided with an external force and when it is released. The so-called circumstances were questioned in a different planet contexts. For this aim, focused group interview method was used. Six focused groups were formed and video recorded during the interval. Each focused group comprised of five pre-service teachers. It was found out pre-service teachers have common misunderstanding and misconceptions. In order to eliminate this conceptual misunderstandings, conceptual change texts were developed and further suggestions were made.

Keywords: computer simulations, conceptual change texts, physics education, students’ misconceptions in physics

Procedia PDF Downloads 466

Authors: Simona Pileviciene

Abstract:

On 24th January 2014, Lithuania notified two primary cases of African swine fever (ASF) in wild boars. The animals were tested positive for ASF virus (ASFV) genome by real-time PCR at the National Reference Laboratory for ASF in Lithuania (NRL), results were confirmed by the European Union Reference Laboratory for African swine fever (CISA-INIA). Intensive wild and domestic animal monitoring program was started. During the period of 2014-2017 ASF was confirmed in two large commercial pig holding with the highest biosecurity. Pigs were killed and destroyed. Since 2014 ASF outbreak territory from east and south has expanded to the middle of Lithuania. Diagnosis by PCR is one of the highly recommended diagnostic methods by World Organization for Animal Health (OIE) for diagnosis of ASF. The aim of the present study was to compare singleplex real-time PCR assays to a duplex assay allowing the identification of ASF and internal control in a single PCR tube and to compare primers, that target the p72 gene (ASF 250 bp and ASF 75 bp) effectivity. Multiplex real-time PCR assays prove to be less time consuming and cost-efficient and therefore have a high potential to be applied in the routine analysis. It is important to have effective and fast method that allows virus detection at the beginning of disease for wild boar population and in outbreaks for domestic pigs. For experiments, we used reference samples (INIA, Spain), and positive samples from infected animals in Lithuania. Results show 100% sensitivity and specificity.

Keywords: African swine fewer, real-time PCR, wild boar, domestic pig

Procedia PDF Downloads 167

Authors: Vikas Kumar, V. H. Saran, Arpit Mathur, Avik Kathuria

Abstract:

The evaluation of biodynamic responses of the human body to whole body vibration exposure is necessary to quantify the exposure effects. A force plate model has been designed with the help of CAD software, which was investigated by performing the modal, stress and strain analysis using finite element approach in the software. The results of the modal, stress and strain analysis were under the limits for measurements of biodynamic responses to whole body vibration. The physical model of the force plate was manufactured and fixed to the vibration simulator and further used in the experimentation for the evaluation of apparent mass responses of the ten recruited subjects standing in an erect posture exposed to vertical whole body vibration. The platform was excited with sinusoidal vibration at vibration magnitude: 1.0 and 1.5 m/s2 rms at different frequency of 2, 3, 4, 5, 6, 8, 10, 12.5, 16 and 20 Hz. The results of magnitude of normalised apparent mass have shown the trend observed in the many past studies. The peak in the normalised apparent mass has been observed at 4 & 5 Hz frequency of vertical whole body vibration. The nonlinearity with respect to vibration magnitude has been also observed in the normalised apparent mass responses.

Keywords: whole body vibration, apparent mass, modeling, force plate

Procedia PDF Downloads 418

Authors: Rodlyn Remina Hines

Abstract:

Africans who migrate to the United States (U.S.) go through an acculturation period. When they join the U.S. workforce during the period they are still acquainting to the new geographic area and culture, they may experience work and family conflict in addition to the stressors of acculturation. This study investigated the impact of acculturation stress and work-family conflict on the health and wellbeing of African immigrants in the U.S. using a growing immigrant population. Ghanaian immigrants (n = 100, males= 43%; females= 56%) residing in New York and Massachusetts, United States (U.S.), were recruited via purposive sampling to investigate the role acculturation stress and work-family conflict play on the health and wellbeing of African immigrants in the U.S. Using the Sociocultural theory, three hypotheses were proposed: (1) High acculturation stress will lead to high work-family conflict, (2) High work-family conflict will result in poor health and wellbeing, and (3) Work-family conflict will mediate the relationship between acculturation stress and health and wellbeing. The results fully supported the first hypothesis and partially supported the second and third. High acculturation stress led to high work-family conflict. Although high work-family conflict resulted in poorer health and wellbeing, high family support mediated work-family conflict and health and wellbeing. Participants who reported poor health also reported a lack of family or other support and those who reported strong family or other support also reported excellent health and wellbeing even with high work-family conflict. The latter group did not expect their health and wellbeing to get worse. I draw on these findings to conclude that African immigrants in the U.S. experience significant acculturation stress and work-family conflict resulting in poor health and wellbeing during their acculturation period if there is a lack of family or other support. These findings have implications for practitioners and policymakers.

Keywords: acculturation stress, work-family conflict, Ghanaian immigrants, health and wellbeing

Procedia PDF Downloads 87

Authors: Sanjay Narayan Deo, Badam Singh Kushvah

Abstract:

Bennu(101955) is a half kilometer potentially hazardous near-Earth asteroid. We analyze the influence of Yarkovsky effect and relativistic effect of the Sun on the motion of the asteroid Bennu. The transverse model is used to compute Yarkovsky force on asteroid Bennu. Our dynamical model includes Newtonian perturbations of eight planets, the Moon, the Sun and three massive asteroid (1Ceres, 2Palas and 4Vesta). We showed the variation in orbital elements of nominal orbit of the asteroid. In the presence of Yarkovsky effect, the Semi-major axis of the orbit of the asteroid is decreases by 350 m over one period of orbital motion. The magnitude of Yarkovsky force is computed. We find that maximum magnitude of Yarkovsky force is 0.09 N at the perihelion . We also found that the magnitude of the Sun relativity effect is greater than the Yarkovsky effect on the motion the asteroid Bennu.

Keywords: Bennu, orbital elements, relativistic effect, Yarkovsky effect

Procedia PDF Downloads 297

Authors: Mahesh Chudasama, Harit Raval

Abstract:

Conical sections and shells of metal plates manufactured by 3-roller conical bending process are widely used in the industries. The process is completed by first bending the metal plates statically and then dynamic roller bending sequentially. It is required to have an analytical model to get maximum bending force, for optimum design of the machine, for static bending stage. Analytical models assuming various stress conditions are considered and these analytical models are compared considering various parameters and reported in this paper. It is concluded from the study that for higher bottom roller inclination, the shear stress affects greatly to the static bending force whereas for lower bottom roller inclination it can be neglected.

Keywords: roller-bending, static-bending, stress-conditions, analytical-modeling

Procedia PDF Downloads 251

Authors: H. Naderpour, R. C. Barros, S. M. Khatami

Abstract:

Seismic excitation is naturally caused large horizontal relative displacements, which is able to provide collisions between two adjacent buildings due to insufficient separation distance and severe damages are occurred due to impact especially in tall buildings. In this paper, an impact is numerically simulated and two needed parameters are calculated, including impact force and energy absorption. In order to calculate mentioned parameters, mathematical study needs to model an unreal link element, which is logically assumed to be spring and dashpot to determine lateral displacement and damping ratio of impact. For the determination of dynamic response of impact, a new equation of motion is theoretically suggested to evaluate impact force and energy dissipation. In order to confirm the rendered equation, a series of parametric study are performed and the accuracy of formula is confirmed.

Keywords: pounding, impact, dissipated energy, coefficient of restitution

Procedia PDF Downloads 357