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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

A comparative study between white and black women entrepreneurs in selected areas in South Africa / Rasego C.

Rasego, Carol Mantwa January 2011 (has links)
Worldwide, entrepreneurship is seen as one of the most important solutions to unemployment, poverty and low economic growth. The creation of new ventures and the growth of existing businesses are vital contributing factors to any economy. Women outnumber male entrepreneurs, which have led to a renewed focus on gender entrepreneurship and the development of appropriate interventions for gender–specific groups across the globe. In South Africa, women make up just less than 50% of the entrepreneurial population. There is therefore, considerable scope to improve the number of women entrepreneurs in the economy and the level at which they operate. Literature review in this study highlighted that female business ownership is concentrated primarily in the service industries where businesses are relatively smaller in terms of employment and revenue, as opposed to the technology, construction and manufacturing sectors. Women entrepreneurs want to expand their businesses as much as male entrepreneurs but women have a hard time in obtaining external financing and credibility as business owners. The objective of the study was to explore white and black women entrepreneurs in the Carletonville and Soweto areas and to provide practical recommendations to ensure successful women entrepreneurship in the country. This study had a total of 58 black and white women entrepreneurs that were motivated by factors like the need for independence, confidence in the product/service offered, self– fulfillment and the need for a challenge into owning a business. A typical woman entrepreneur in this study is between the ages 40 to 59 years, is married with an average of one to two children. The woman entrepreneur is fairly educated with an education level of matric and a diploma. But her business is micro or very small with an annual turnover of R50 000 to R500 000. Participating women entrepreneurs are faced with obstacles such as inequality of access to credit, awareness and access to business support, risk averse, lack of focused women entrepreneurship policies from regional municipalities and government, lack of education and training in their business start–up phase. They are faced with obstacles such as awareness / access to business support, gaining acceptance and respect of people, liquidity and other financial problems and lack of timely business information in running their businesses. Women entrepreneurs in this study declared that they need support on factors such as business advice, information, counselling, mentoring, marketing support and women entrepreneurship specific based policies to enhance women entrepreneurship in the areas of Soweto and Carletonville. The study also conducted t–tests to compare white and black women entrepreneurs in the Carletonville and Soweto areas. The t–tests focused on motivational factors to self– employment, obstacles to business start–up and obstacles faced in current business operations. The t–test in this study revealed that black women entrepreneurs rated the following motivating factors: desire to wealth, the need for independence, need for flexible work schedule, need for a challenge, self–fulfillment, to develop my hobby, insufficient family income and ensure high job security more positively than the white women entrepreneurs. In addition, the t–tests also revealed that black women entrepreneurs are affected more than the white entrepreneurs by fear of failure and their perceived inequality of access to credit in their business start–up. Furthermore, black women entrepreneurs, in running their businesses are severely affected by family pressures in relation to gender roles and a lack of awareness of or access to business support more than the white women entrepreneurs. This study offered recommendations such as exposing women in entrepreneurship at a tender age, increasing access to finance and the establishment and enhancement of women entrepreneurs’ organisations like SAWEN, BWASA, and SAWIMA amongst others. The women entrepreneurs’ organisations should embark on campaigns and intensify their marketing strategies amongst others. / Thesis (M.B.A.)--North-West University, Potchefstroom Campus, 2012.
132

Obstacle detection using a monocular camera

Goroshin, Rostislav January 2008 (has links)
Thesis (M. S.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2008. / Committee Chair: Vela, Patricio; Committee Member: Collins, Thomas; Committee Member: Howard, Ayanna
133

Women, are we our own barriers when making careers?

Sarmiento, Andrea, Sassus, Julie January 2008 (has links)
<p>The scarcity of female leaders rise curiosity to explore the reasons of the phenomenon. Many attempts have been done to explain the scarcity but somehow it seems that investigations explore the same factors and not what has been seen as a taboo; women’s feelings and thoughts towards each other as obstacles in making careers. Therefore is the aim of this study: to gain knowledge about women’s feelings and thoughts about other women in a corporate environment to be able to draw conclusions whether this matter can be a contribution to the debate concerning obstacles for women to climb in their career.</p><p>This research is conducted through an inductive approach with eight qualitative interviews choosing both women leaders and non-leaders. Jealousy and envy between women were discovered, which do not seem to restrain or create obstacles for other women but only or mostly, to women having these feelings and thoughts. Jealousy and envy are just a symptom of the real problem which is poor selfconfidence in the corporate environment. We discovered a vicious circle which shows us the connection between jealousy, self-confidence, competition and success. The vicious circle could be an input to the debate to explain obstacles that women could meet in their path to leading positions.</p><p>Women have to start believing in themselves with help of society where she is not directly or indirectly restrained for the fact of being a woman.</p>
134

Οι δυσκολίες που αντιμετωπίζουν οι μεταπτυχιακοί φοιτητές του Ελληνικού Ανοικτού Πανεπιστημίου κατά την εκπόνηση της διπλωματικής τους εργασίας

Μπαλοπούλου, Βασιλική 01 February 2013 (has links)
Σκοπός της εργασίας ήταν η διερεύνηση των δυσκολιών που αντιμετώπισαν οι μεταπτυχιακοί φοιτητές του ΕΑΠ κατά την εκπόνηση της διπλωματικής τους εργασίας και συγκεκριμένα οι μεταπτυχιακοί φοιτητές/τριες της ενότητας ΕΚΠ65. Στην έρευνα συμμετείχαν 18 μεταπτυχιακοί φοιτητές/τριες της ενότητας ΕΚΠ65,οι οποίοι εκπονούσαν την εργασία τους κατά το ακαδημαικό έτος 2010-11. Πρόκειται για μια ποιοτική προσέγγιση στην οποία χρησιμοποιήθηκε ως ερευνητικό εργαλείο η μη δομημένη συνέντευξη με ερωτήσεις ανοιχτού τύπου. Τα αποτελέσματα έδειξαν πως οι φοιτητές/τριες συνάντησαν μια πληθώρα δυσκολιών/εμποδίων με πιο χαρακτηριστικά τα ακόλουθα: επαγγελματικές και οικογενειακές υποχρεώσεις, περιορισμένος διαθέσιμος χρόνος, προβλήματα υγείας, δυσκολία εξεύρεσης βιβλιογραφίας, δυσκολίες στην μεθοδολογία-συγγραφή έρευνας, στην επιλογή και διατύπωση θέματος, προβλήματα στην επικοινωνία με τον επιβλέποντα καθηγητή,δυσκολίες στην στατιστική επεξεργασία δεδομένων, μεγάλος όγκος βιβλιογραφίας, γεωγραφική απομάκρυνση-απόσταση απο βιβλιοθήκες, ψυχολογικοί παράγοντες, όπως το άγχος και τέλος, προσωπικοί λόγοι-γάμος. / The purpose of this paper is the definition of the difficulties that are faced by the EKP65 unit's postgraduate students of the Hellenic Open University, while they prepared their Master thesis. Eighteen postgraduate students participated in the research in the academic year 2010-11. It is a qualitative approach, in which semi-structured interview and open questions were used. The results of this research revealed that the students faced an amoumt of difficulties and obstacles. The most frequently spotted were: proffesional and family obligations, lack of time, helth problems, finding topic, problems in the bibliography research, difficulties in the writing process, communication issues with thw surervisor, statistical analysis of their data, many reading obligations, geografical distance from the libraries, psychological parametres.like anxiety and personal reasons-marriage.
135

Möjligheter och begränsningar med utomhusmiljön i förskolan / Opportunities and obstacles with the outdoor environment in preeschool

Lönn, Niklas January 2015 (has links)
Studiens syfte är att belysa hur några pedagoger ser på utomhusmiljön. Studien utgår ifrån följande frågeställningar: Vilka möjligheter kan pedagogerna se i att använda sig utav utomhusmiljön i verksamheten? Vilka begränsningar kan pedagogerna se i att använda sig utav utomhusmiljön i verksamheten? Vilka argument finns för att gå ut och när går man ut?Studien är genomförd med ljudinspelade besöksintervjuer för att nå ett så tillförlitligt och trovärdigt resultat som möjligt. I studien ingår fem förskollärare på fyra olika förskolor. Urvalet är med hänsyn till såväl intresset från respondenter som tidsaspekten att tre av förskolorna ligger i samma kommun för att minimera restiden.Det som synliggjorts i resultatet är att samtliga intervjuade pedagoger ser stora möjligheter, men även begränsningar, i användandet av utomhusmiljön. En möjlighet som nämns är pedagogernas möjlighet att erbjuda barnen lärtillfälle i såväl naturen som på förskolegården. En begränsning som samtliga pedagoger nämner är ekonomin och tiden i verksamheten, då verksamheten är beroende av pengar för införskaffandet av artefakter och tiden för att underhålla och genomföra alla idéer som finns för konstruktionen och användning av utomhusmiljön. Pedagogerna belyser barnens hälsovinst som argument för varför de går ut, men även hur förskolans traditioner och dess inrutade arbetssätt gör att de går ut vid vissa klockslag.
136

Complexidade do ambiente e assimetria no andar de idosos com doença de Parkinson / Complexity of the environment and asymmetry on the gait in patients with Parkinson's disease

Orcioli-Silva, Diego [UNESP] 18 December 2015 (has links)
Submitted by DIEGO ORCIOLI DA SILVA null (diego_orcioli@hotmail.com) on 2016-01-26T20:23:30Z No. of bitstreams: 1 Dissertação_Orcioli-Silva.pdf: 2125935 bytes, checksum: 70f39e06a5152e7798496d596456cdd6 (MD5) / Approved for entry into archive by Sandra Manzano de Almeida (smanzano@marilia.unesp.br) on 2016-01-27T12:18:10Z (GMT) No. of bitstreams: 1 orciolisilva_d_me_rcla.pdf: 2125935 bytes, checksum: 70f39e06a5152e7798496d596456cdd6 (MD5) / Made available in DSpace on 2016-01-27T12:18:10Z (GMT). No. of bitstreams: 1 orciolisilva_d_me_rcla.pdf: 2125935 bytes, checksum: 70f39e06a5152e7798496d596456cdd6 (MD5) Previous issue date: 2015-12-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Introdução: A presente dissertação de mestrado é composta por dois estudos. O Estudo 1 analisou e comparou a influência do aumento da complexidade do ambiente nos parâmetros cinemáticos e cinéticos do andar de idosos com doença de Parkinson (DP) e idosos neurologicamente sadios. O Estudo 2 analisou e comparou a assimetria do andar de idosos com DP e idosos neurologicamente sadios em ambientes com múltiplos obstáculos. Materiais e método: A amostra do estudo foi composta por 38 idosos, sendo 19 idosos com DP e 19 idosos sadios. A tarefa experimental consistiu em andar em velocidade preferida nas seguintes condições: sem ultrapassagem de obstáculo; com ultrapassagem de um obstáculo; com ultrapassagem de dois obstáculos a 108cm de distância entre eles (Estudo 1), ainda, no Estudo 2 foi acrescentada a condição com ultrapassagem de dois obstáculos a 50cm de distância entre eles. No Estudo 1, a ultrapassagem foi realizada com o membro inferior direito e, no Estudo 2, com ambos os membros inferiores. Para o andar sem obstáculo, foi analisada a passada central. Nas condições com obstáculo(s) foram analisadas as fases de aproximação e ultrapassagem, sendo que, na condição com dois obstáculos, a análise foi realizada apenas para o primeiro obstáculo. No Estudo 1 foram analisados os parâmetros cinemáticos e cinéticos do andar e no Estudo 2 foi calculado o Índice de Assimetria para cada variável do andar. Resultados: Estudo 1: os idosos diminuíram o comprimento da passada nas condições com 1 e 2 obstáculos e, na condição com 2 obstáculos, aumentaram a duração da passada. Ainda, os idosos com DP diminuíram a porcentagem em suporte simples e aumentou o duplo suporte em ambas as condições com obstáculos. Na fase de ultrapassagem, a presença de 2 obstáculos no andar exigiu ajustes cinemáticos e cinéticos (menor comprimento e velocidade do passo, menor distância horizontal e vertical entre o pé e o obstáculo e menor impulso horizontal de frenagem) mais acentuados comparado às outras condições. Estudo 2: os idosos com DP aumentaram a assimetria na fase de aproximação, especialmente nas variáveis temporais do passo (duração e fase de balanço do passo), nas condições com múltiplos obstáculos. Na fase de ultrapassagem, os idosos com DP apresentaram maior assimetria na distância vertical do pé para o obstáculo. Conclusão: Os idosos realizam ajustes nos parâmetros do andar em ambientes com obstáculos. Devido à maior exigência motora, atencional e sensorial do ambiente com múltiplos obstáculos, os idosos aumentaram a duração da passada na fase de aproximação, demonstrando a necessidade de mais tempo para processar as informações do ambiente. Contudo, devido aos déficits na integração sensório-motora e comprometimentos motores dos idosos com DP, o andar em ambientes mais complexos é mais prejudicial para essa população, exacerbando a bradicinesia e a hipometria. Por fim, os idosos com DP apresentam maior assimetria no andar quando comparados a idosos sadios em ambiente com múltiplos obstáculos, principalmente na fase de aproximação. / Introduction: This dissertation consists of two studies. Study 1 investigated the influence of environmental complexity on kinematic and kinetic parameters of gait in people with Parkinson's disease (PD) and healthy older adults. Study 2 compared gait asymmetry between people with (PD) and healthy older adults while walking on an environment with multiple obstacles. Materials and method: Thirty-eight older adults (19 patients with PD and 19 healthy individuals) participated in the study. The experimental task required participants to walk at preferred speed under the following conditions: free (regular) walking, avoiding one obstacle, avoiding two obstacles placed 108cm apart (Study 1); in the Study 2, another experimental condition was added: avoiding two obstacles placed 50cm apart. In the Study 1, obstacle avoidance was performed with the right limb as the leading limb, while both limbs were used as the leading limb for the Study 2. For free walking condition, the stride cycle performed in the central area of the pathway was considered for analysis. For conditions with two obstacles, outcome measures included calculations related to the first obstacle only, considering both approach and crossing phases. In the Study 1, we calculated kinematic and kinetic parameters of walking; in the Study 2, we calculated the asymmetry index for each outcome measure. Results: Study 1: both people with PD and healthy individuals decreased the stride length while approaching obstacles (one or two) and increased stride duration while approaching two obstacles. Also, people with PD decreased the percentage of time spent in single support and increased the time spent in double support in both condition with one and two obstacles. For the crossing phase, the presence of 2 obstacles in the pathway required more evident kinematic and kinetic adjustments (decreases were observed for step length, step velocity, horizontal and vertical distances from the feet to the obstacle, and horizontal braking impulse) in comparison to the other experimental conditions. Study 2: people with PD increased asymmetry of walking in the approach phase, especially for temporal outcomes (step duration and swing phase) in the conditions with multiple obstacles. For the crossing phase, people with PD demonstrated higher asymmetry values than healthy older adults for toe clearance. Conclusion: both people with PD and healthy individuals were able to adapt walking behavior when faced with environmental constraints induced by obstacles. Due to increased attentional and sensorimotor requirements to succeed while walking in environments with multiple obstacles, both people with PD and healthy participants increased stride duration in the approach phase, suggesting that additional time is necessary to process information from the environment in this situation. However, due to deficits in sensorimotor integration and motor impairments of PD, walking in more complex environments is more harmful to patients with PD, exacerbating bradykinesia and hypometria. Lastly, people with PD demonstrated higher asymmetry of walking than healthy individuals in environment with multiple obstacles, especially in the approach phase. / FAPESP: 2013/27032-0
137

The challenges facing women entrepreneurs : a study on Gulf Cooperation Council (GCC) countries

Taqi, Najma January 2016 (has links)
Women’s entrepreneurship is a much touted topic of research with researchers competing to contribute to the growing body of knowledge. Although literature is replete with articles and opinions on the various aspects concerning women’s entrepreneurship, still more needs to be done. Much of the research produced until now has focused on specific contexts like western countries and results obtained are either not conclusive or generalizable and in many cases incomplete. Research on women’s entrepreneurship conducted in the contexts of developing nations appears to be grossly inadequate, bordering almost on a neglected category. Specifically, research on women’s entrepreneurship conducted in the context of Gulf Cooperation Council (GCC) Countries is almost nil except for a few sporadic articles here and there. How women entrepreneurs have fared in the GCC countries is not clear and there is a need to know what their current status is, how they have performed and what challenges contribute to their lack of progress. There is a huge gap in the literature in this area and this research has made some modest contributions to remove this gap partially. The literature review shows that a number of challenges affect women entrepreneurs’ success. Although the research output used in this research was derived from studies conducted largely in a western context, some of the factors grounded in theories like institutional theory were found to be applicable to the context of women entrepreneurs in the GCC. Five of these challenges, namely lack of adequate training and education; legal constraints; cultural constraints and a lack of social support; lack of access to financial resources; and work–family interface have been investigated in this research using a conceptual model and survey questionnaire. Women entrepreneurs in three GCC countries, namely Kingdom of Bahrain, Saudi Arabia and the United Arab Emirates, were chosen for studying the phenomenon of women’s entrepreneurial involvement in business activities. A random sampling method was used. Hypotheses were developed and verified and the five challenges were found through rigorous statistical tests to significantly affect the involvement of women entrepreneurs in business activity in GCC countries. The challenges selected were part of a larger set of challenges, not all of which could be investigated due to paucity of time, resources and the large territory comprising three nations in the GCC region. In addition, an exploratory study using interviews was conducted to identify specific challenges that affect women entrepreneurs in the GCC countries. Three additional challenges, namely intellectual property; patronage and connections; and lengthy regulatory procedures were revealed through this. Mixed method research was used which led to triangulation of the results obtained from analysing data gathered through questionnaire survey and interview. The challenges that emerged from the analysis of the questionnaire survey and interviews resulted in the development of a new and comprehensive model that combined the challenges tested through the empirical model and those derived from interviews. The findings from the analysis indicated that much needs to be done to enable women entrepreneurs involved in business activities in the GCC region to succeed. Many challenges need to be tackled. The findings clearly point out that the challenges are responsible for the low percentage (around 2%) of business activities attributable to women-owned enterprises in the GCC countries. This research contributes to the growing body of knowledge in the area of women’s entrepreneurship in the specific context of the GCC region. The research outcomes clearly indicate that specific challenges can be tackled to improve the involvement of business activities of women entrepreneurs in the GCC region. Since the topic of involvement of women entrepreneurs in business activities in the context of GCC countries is not well investigated, the research outcomes of this research add to the current knowledge from a contextual point of view. In addition, the research has expanded the application of institutional theory to understand about the various challenges that affect involvement of women entrepreneurs in business activities in the context of GCC and contributed theoretically in terms of developing a new framework that could be used to examine how the challenges could be tackled. Methodologically, the research has shown how a mixed method research can be used to combine the outcome of survey research with interviews. Practical implications of the research outcomes show that the framework developed in this research could be adopted in practice by women entrepreneurs themselves, as well as various institutions and organizations that are concerned with women entrepreneurs, for improving the involvement of women entrepreneurs in business activities in the context of the GCC. Although the limitations of this research have been highlighted, how to overcome those limitations through future research has been explained. Thus, overall, this research effort is expected to stimulate further discussion and debate with regard to the involvement of women in business activities in the GCC and act as some kind of a basis for initiating steps to improve the position of women entrepreneurs involved in business activities in the GCC and perhaps in other regions surrounding the GCC countries.
138

Student bortom campus : En kvalitativ studie baserad på intervjuer med studenter om att distansstudera på universitetsnivå / Student beyond campus

Andersson, Petra, Theresa, Lindahl January 2018 (has links)
Med alltmer digitalisering i samhället ökar distansutbildningarna fort och erbjuds idag på de flesta lärosäten. Allt fler väljer att studera på distans därför handlar denna studie om att undersöka varför man väljer att studera på distans, vilka hinder som distansstudenten kan uppleva och hur lärosätets upplägg upplevs av distansstudenter, då dessa påverkar studentens möjligheter att genomföra och slutföra sina studier på ett bra sätt. Studien utfördes genom semistrukturerade intervjuer med åtta distansstudenter.Studiens resultat visar tydligt att lärosätens upplägg, kommunikation och tillgänglighet är viktigt för framgång, men också att motivation och självdisciplin från studentens sida också spelar stor roll för att kunna genomföra och slutföra studierna. / Today, with more digitization in society the distance education increases fast and is available at most universities. More people choose to study at a distance why this study was made to examine what obstacles and how the University's approach is experienced by distance students, as this affects the student's ability to carry out and complete their studies in a good way. The study was conducted by means of semi-structured interviews with 8 distance students.The results of the study clearly shows that how the seat of learnings platform, communication and availability are important for success, but also the motivation and self-discipline from the student's side also plays a major role in order to carry out and complete their studies.
139

Firm performance versus perception of obstacles: evidence for Brazil, Chile and Peru / Desempenho das firmas versus percepÃÃo de obstÃculos: evidÃncias para Brasil, Chile e Peru

Jefferson Ricardo do Amaral Melo 26 February 2015 (has links)
nÃo hà / Desempenho das firmas podem ser afetados por um conjunto de obstÃculos, sendo eles intrÃnsicos à prÃpria firma como tamanho, setor, e estrutura organizacional da firma, ou determinados pelo contexto econÃmico e social do paÃs em que a mesma se encontra. A percepÃÃo que o empresÃrio possui das dificuldades contextuais podem direcionar os investimentos em qualquer sentido, fazendo com que empresas iguais tomem decisÃes diferentes. Esta dissertaÃÃo investiga como percepÃÃes de diferentes tipos obstÃculos contextuais podem afetar a performance das firmas em diferentes paÃses da America do Sul: Brasil, Chile e Peru. Para isso utilizou-se como indicadores de performance os investimentos em ativos fixos, capacidade de utilizaÃÃo de recursos, crescimento de vendas e contrataÃÃes de trabalhadores. Os obstÃculos contextuais considerados foram os de cunho institucionais/legais tais como: carga tributÃria, licenÃas e regulamento do trabalho; sociais: corrupÃÃo, crime e competiÃÃo com setor informal; econÃmicos: mÃo-de-obra nÃo qualificada e acesso a financiamento e de infraestrutura: acesso a eletricidade e transporte. Os dados da pesquisa foram extraÃdos do site do Banco Mundial, pesquisa enterprise surveys. Para fazer as estimaÃÃes foram utilizados os modelos de regressÃo linear e logistica conforme a variÃvel dependente. Os principais resultados mostraram que obstÃculos econÃmicos e sociais sÃo comuns aos trÃs paÃses estudados. Cabe destacar que alÃm de obstÃculos comuns aos trÃs paÃses, para o Chile e Peru, obstÃculos Institucionais/legais parecem tambÃm influenciar o desempenho das empresas daqueles paÃses. / Firms' performance may be affected by a number of obstacles, they are intrinsic to the Firm as size, sector, and organizational structure of the firm, or determined by the social and economic context of the country in which it is located. The perception that the entrepreneur has the contextual difficulties can direct investments in any direction, making the same companies take different decisions. This dissertation investigates how perceptions of different types contextual obstacles can affect the performance of firms in different countries of South America: Brazil, Chile and Peru. For this was used as performance indicators fixed asset investment, resource capacity utilization, sales growth and hiring workers. Contextual obstacles were considered the institutional / legal nature such as taxes, licenses and regulation of labor; Social: corruption, crime and competition from the informal sector; economic: unskilled labor and access to funding and infrastructure: access to electricity and transportation. The survey data were extracted from the World Bank website, research enterprise surveys. To make estimates of the linear and logistic regression models were used as the dependent variable. The main results showed that economic and social obstacles are common to the three countries studied. It should be noted that in addition to common obstacles to the three countries, to Chile and Peru, obstacles Institutional / Legal also seem to influence the performance of companies in those countries.
140

Estudo e aplicação do referencial bachelardiano de obstáculos epistemológicos no ensino de sistemas químicos oscilantes / Study and aplication of referential bachelardean to teaching oscillating chemical systems

André Luís Martins 20 September 2013 (has links)
O estudo e observação de Sistemas Químicos Oscilantes vêm se destacando como importante campo de pesquisa da ciência química contemporânea. Tais sistemas têm como comportamento notório principal a variação periódica da concentração de um intermediário de reação química. Sua compreensão vem estimulando debates que transcendem o escopo químico e estabelecem relações com outras disciplinas científicas, e mais marcadamente, o estudo de sistemas complexos em geral. O ensino de sistemas químicos oscilantes, em específico, e de sistemas complexos, em geral, se apresenta na atualidade como desafio necessário e estimulante. Neste trabalho optou-se por tentar contribuir neste esforço, utilizando-se da noção de obstáculos epistemológicos inicialmente estabelecida pelo filósofo francês Gastón Bachelard. O conceito de obstáculos epistemológicos apresentou-se nas últimas décadas como importante ferramenta na abordagem das relações de ensino-aprendizagem de conceitos das ciências contemporâneas. Existem diferentes tipos de obstáculos epistemológicos, entre eles: experiência primeira, conhecimento geral, obstáculo verbal, conhecimento unitário e pragmático e obstáculo animista. Neste trabalho surge a proposta de utilizar a noção de obstáculo epistemológico voltada ao ensino de conceitos da complexidade pertinentes aos Sistemas Químicos Oscilantes. Foram analisadas as presenças de obstáculos epistemológicos em textos didáticos de ensino de sistemas químicos oscilantes. Os textos didáticos escolhidos foram artigos científicos da área de ensino de química voltados ao ensino de sistemas químicos oscilantes, livros didáticos usados em cursos de graduação e livros de divulgação científica. Foram analisados os conteúdos integrais de sete artigos científicos da área de ensino de química voltados ao tema reações químicas oscilantes. Foram também analisadas as seções referentes a reações químicas oscilantes de quatro livros didáticos utilizados em cursos de graduação da USP devotadas ao ensino de sistemas caóticos. Foram também analisadas as seções referentes a reações químicas oscilantes de quatro livros de divulgação científica que abordaram o tema sistemas químicos oscilantes. Foram encontrados grande número de obstáculos da experiência primeira e obstáculos animistas em livros didáticos e um grande número de obstáculos verbais em livros de divulgação científica. Todos os tipos de obstáculos epistemológicos listados foram identificados ao menos uma vez em algum dos textos. Demonstrou-se a viabilidade de aplicação do conceito de obstáculos epistemológicos em textos didáticos de ensino de sistemas químicos oscilantes. / The study and observation of Oscillating Chemical Systems have been highlighted as an important research field of chemical science contemporary. Such systems are notorious behavior as the main periodic variation of the concentration of an intermediate chemical reaction. Your understanding is stimulating debates that transcend the scope of chemical and establish relationships with other scientific disciplines, and most notably, the study of complex systems in general. The teaching of chemical oscillating systems, in particular, and complex systems in general, is presented nowadays as necessary and stimulating challenge. In this work it was decided to try to contribute in this effort, using the notion of epistemological obstacles initially established by the philosopher Gaston Bachelard. The concept of epistemological obstacle presented itself in recent decades as an important tool in addressing the relationships of teaching and learning of contemporary science concepts. There are different kinds of epistemological obstacles, among them: first experience, geral knowledge, verbal obstacle, pragmatic and unitary knowledge and animist obstacle . This work comes propose to use the notion of epistemological obstacle to teach the complexity of concepts relevant to oscillating chemical system .We analyzed the presence of epistemological obstacles in textbooks that have teaching oscillating chemical systems. The selected texts were scientific articles in the area of chemical education aimed at teaching oscillating chemical systems, books used in undergraduate and some popular science books. We analyzed the entire contents of seven papers in the area of chemical education geared to the theme oscillating chemical reactions. We also analyzed the sections pertaining to oscillating chemical reactions of four textbooks used in undergraduate courses devoted to teaching the chaotic systems at USP . We also analyzed the sections pertaining to oscillating chemical reactions of four popular science books that addressed the issue of oscillating chemical systems. We found many first experiences and animists obstacles in textbooks and a large number of verbal obstacles in popular science books. All kinds of epistemological obstacles identified were listed at least once at some of the texts. The results confirm the feasibility of applying the concept of epistemological obstacles in textbooks teaching oscillating chemical systems.

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