Download or read book Extremely Low Frequency Magnetic Fields in Electrical Substations and Residential Areas of Mangaung Metropolitan Municipality written by Phoka Caiphus Rathebe and published by . This book was released on 2016 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the beginning of the twenty first century electricity has become an integral part of every human‟s life. Without electricity some of the human activities on planet earth would have never been brought into existence and some of them will not be possible (Fews, 1999). Electricity is supplied to old and current technology apparatus such as computers, different types of machinery, laboratory and medical devices, household appliances, automobiles, and treatment plant equipment. Electricity moves from power generation plants (power stations) in a form of high voltage to urban and rural electrical substations where it will be converted into low voltage to suit residential electrical processes (Ilonen, 2008). According to Kaune (1993), high voltage electricity moves through overhead and underground power lines and it is converted into low voltage once it reaches electrical distribution substations in the residential areas. Furthermore, electrical substations serve many functions, such as controlling, collecting and transferring power on electrical systems (Kaune, 1993). Along the transportation and conversion of voltages, the two invisible fields known as magnetic and electric fields are produced (Kovetz, 2000). Both magnetic and electric fields are produced by movement of charged and stationary electrical particles as described in the Maxwell‟s equation (Lee, 1996). These fields are expressed in hertz (Hz) and can be classified as very low frequency (VLF), low frequency (LF), extremely low frequency (ELF) and high frequency fields (HFF) (Brent, 1999). Extremely low frequency (ELF) magnetic fields are fields with frequency that ranges between 3 to 3000 Hz and they are usually formed when the electrical current flows (World Health Organisation, 2007). According to Sinatra (2002), once there is higher current flow during conversion or transmission, high voltages are produced as a result of increased magnetic field flux. High voltages are mainly used when transferring power over long distances from generation plants to final distribution substations (Portier and Wolfe, 1998). When electricity is being transferred and has reached distribution substations, the intensity of the electric and magnetic fields changes. Lacy-Hulbert, Metcalfe and Hesketh (1998) indicated that an intensity of electric fields created is determined by the amount of voltages transferred and the flow of current determines the magnitude of magnetic fields that will be produced. The force of both magnetic and electric fields is induced by different substation devices which include wirings, cables and installations. According to the National Institute for Environmental Health (NIEH) (2002), most substations use alternating current (AC) in distributing and converting current, which produces magnetic and electric fields at various magnitude levels. The level of exposure to magnetic fields is determined by the distance between the source and the receiver (Portier and Wolfe, 1998). According to Loomis and Savitz (1995), individuals in close proximity to distribution substations are more likely to be exposed to high levels of magnetic fields than those residing far from them. Individuals exposed to magnetic fields are likely to develop detrimental health effects, such as childhood leukaemia. However there is still controversy on this matter (Draper, 2005).
Download or read book Power Frequency Magnetic Fields and Public Health written by William F. Horton and published by CRC Press. This book was released on 1995-06-27 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: The prospect that electromagnetic fields (EMFs) may foster disease is an alarming thought-one which raises such questions as: What are these invisible forces? How are they produced? Is there conclusive evidence that they are harmful to the human body? How do we protect ourselves against possible harm from them? This book addresses these and other questions about magnetic fields, bringing together in a single reference source the scientific background, current status of health research, and means to reduce the impact of EMFs in our environment. Important information is provided for developing policies and procedures related to human interaction with magnetic fields. The authors describe the concept of prudent avoidance, emphasizing its value as a tool in the design, construction, and valuation of homes, offices, retail facilities, and factories. The book provides theory, computer simulation results, measured data, and recommendations for magnetic field management, all of which are useful as a power system design and construction resource. The authors have compiled an impressive summary of the studies, findings, and reports done in the past 15 years in the areas of human health effects which might be attributed to exposure to power frequency magnetic fields. Wherever appropriate throughout text, the authors provide examples to illustrate concepts and include end-of-chapter exercises (with solutions) to help readers solidify their understanding of the material presented. Originally designed as a textbook, this is also an excellent reference in the areas of environmental engineering, city and regional planning, and electrical engineering.
Download or read book Occupational and Non occupational Exposures to Extremely Low Frequency ELF Magnetic Fields in Selected Electric Power Substations in the Philippines written by Victor Angelo C. Margallo and published by . This book was released on 2009 with total page 79 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Youth Employment Patterns written by and published by . This book was released on 1985 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Doing Research written by Laetus O. K. Lategan and published by AFRICAN SUN MeDIA. This book was released on 2011-01-01 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book was written by authors with a passion for research development with the purpose of giving novice researchers a holistic view of what they will encounter when doing research. The interplay between scientific theory, academic research and professional practice has been highlighted as these are considered the cornerstones to be mastered as early as possible in a young researcher's career.
Download or read book Conservation Biology in Sub Saharan Africa written by Richard Primack and published by Open Book Publishers. This book was released on 2019-09-10 with total page 712 pages. Available in PDF, EPUB and Kindle. Book excerpt: Conservation Biology in Sub-Saharan Africa comprehensively explores the challenges and potential solutions to key conservation issues in Sub-Saharan Africa. Easy to read, this lucid and accessible textbook includes fifteen chapters that cover a full range of conservation topics, including threats to biodiversity, environmental laws, and protected areas management, as well as related topics such as sustainability, poverty, and human-wildlife conflict. This rich resource also includes a background discussion of what conservation biology is, a wide range of theoretical approaches to the subject, and concrete examples of conservation practice in specific African contexts. Strategies are outlined to protect biodiversity whilst promoting economic development in the region. Boxes covering specific themes written by scientists who live and work throughout the region are included in each chapter, together with recommended readings and suggested discussion topics. Each chapter also includes an extensive bibliography. Conservation Biology in Sub-Saharan Africa provides the most up-to-date study in the field. It is an essential resource, available on-line without charge, for undergraduate and graduate students, as well as a handy guide for professionals working to stop the rapid loss of biodiversity in Sub-Saharan Africa and elsewhere.
Download or read book Decolonisation and Regional Geopolitics written by Lazlo Passemiers and published by Routledge. This book was released on 2019-03-11 with total page 231 pages. Available in PDF, EPUB and Kindle. Book excerpt: Decolonisation and Regional Geopolitics argues that as much as the ‘Congo crisis’ (1960-1965) was a Cold War battleground, so too was it a battleground for Southern Africa’s decolonisation. This book provides a transnational history of African decolonisation, apartheid diplomacy, and Southern African nationalist movements. It answers three central questions. First, what was the nature of South African involvement in the Congo crisis? Second, what was the rationale for this involvement? Third, how did South Africans perceive the crisis? Innovatively, the book shifts the focus on the Congo crisis away from Cold War intervention and centres it around African decolonisation and regional geopolitics.
Download or read book Believe that All Can Achieve written by Juan Bornman and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Every learner and every teacher is a unique blend of personal characteristics and background factors that change with time and context, and affect the experience of living and developing. Traditionally, the education of children with disabilities focused on the nature of specific conditions in an attempt to alleviate barriers to learning. The disability, and not the impact of the impairment on participation at school or at home, was emphasized. The current focus is on the strengths, attitudes and positive functioning of children within meaningful contexts. Believe that all can achieve addresses inclusion as the foundation for education in an attempt to celebrate diversity in the classroom, to capitalize on the strengths each learner brings to the learning-teaching dyad, and to welcome every family member as part of the broader classroom community."--Cover
Download or read book Writing the Ancestral River written by Jacklyn Cock and published by Wits University Press. This book was released on 2018-03-01 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: Writing the Ancestral River is an illuminating and unusual biography of the Kowie River in the Eastern Cape. This tidal river runs through the centre of what used to be called the Zuurveld, a formative meeting ground of different peoples who have shaped our history: Khoikhoi herders, Xhosa pastoralists, Dutch trekboers and British settlers. Their direct descendants continue to live in the area and interact in ways that have been decisively shaped by their shared history. Besides being a social history, this is also a natural history of the river and its catchment area, where dinosaurs once roamed and cycads still grow. As the book shows, the natural world of the Kowie has felt the effects of human settlement, most strikingly through the establishment of a harbour at the mouth of the river in the 19th century and the development of a marina in the late 20th century. Both projects have had a decisive and deleterious impact on the Kowie. People are increasingly reconnecting with nature and justice through rivers. Acknowledging the past, and the inter-generational, racialised privileges, damages and denials it established and perpetuates, is necessary for any shared future. By focusing on this `little' river, the book raises larger questions about colonialism, capitalism, `development' and ecology, and asks us to consider the connections between social and environmental injustice.
Download or read book Science Policy and Development in Africa written by R. Sooryamoorthy and published by Cambridge University Press. This book was released on 2022-09-01 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since gaining political independence in the 1950s, science has rapidly become a prerequisite for national development within many African nations. Supported by international agencies, such as UNESCO, initiatives were taken to direct Africa on the road of scientific development, enabling contributions to world science and significant progress in many specific research areas. However, from a developmental perspective there remains the question of how science influences national development plans and strategies. How far are science policies integrated into the national development plans? What potential and challenges do science and technology pose for Africa and its prospects for wider development? Offering a comprehensive historical and empirical study of science in both colonial and post-colonial Africa, R. Sooryamoorthy brings to light the connections between science, policy and development in African nations. Focusing on understanding the widening gap in science and technology between developed and developing regions, and the integration (or lack of) with national development strategies, this study provides important insights into the potential opportunities and challenges facing Africa in the areas of science.
Download or read book Biometric State written by Keith Breckenridge and published by Cambridge University Press. This book was released on 2014-10-02 with total page 265 pages. Available in PDF, EPUB and Kindle. Book excerpt: A groundbreaking study of South Africa's role as a site for global experiments in biometric identification throughout the twentieth century.
Download or read book Retail Worker Politics Race and Consumption in South Africa written by Bridget Kenny and published by Springer. This book was released on 2018-05-23 with total page 289 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book argues that we need to focus attention on the ways that workers themselves have invested subjectively in what it means to be a worker. By doing so, we gain an explanation that moves us beyond the economic decisions made by actors, the institutional constraints faced by trade unions, or the power of the state to interpellate subjects. These more common explanations make workers and their politics visible only as a symptom of external conditions, a response to deregulated markets or a product of state recognition. Instead – through a history of retailing as a site of nation and belonging, changing legal regimes, and articulations of race, class and gender in the constitution of political subjects from the 1930s to present-day Wal-Mart – this book presents the experiences and subjectivities of workers themselves to show that the collective political subject ‘workers’ (abasebenzi) is both a durable and malleable political category. From white to black women’s labour, the forms of precariousness have changed within retailing in South Africa. Workers’ struggles in different times have in turn resolved some dilemmas and by other turn generated new categories and conditions of precariousness, all the while explaining enduring attachments to labour politics.
Download or read book Improving Public Policy for Good Governance written by Fanie Cloete and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Essentially, good governance is the primary mission of the public sector. Effective policy management is a crucial component of good governance if the desired improvements in society are to be achieved. A thorough understanding of the nature, content, processes and outcomes of public policy is not only imperative for continually improving public sector governance, but also vital for establishing good public management on a daily basis. The fourth edition of Improving public policy for good governance has been updated and revised substantially. It focuses on integrating the functionally specialised agencies of government, business, labour and civil society into a holistic and efficient policy network. This is necessary in an attempt to deal with the complexities of transformational leadership while addressing optimal development and public services delivery in society, amidst an ever advancing digital era that is under increasing resource constraints. This book bridges the theory and practice of public policy by linking them in a user-friendly manner. It explains what public policy is and should be, why and how it is created, and how public policy content, processes, outputs and outcomes can be improved to promote optimal good governance. Furthermore, it shows how to achieve sustainable developmental goals in the information society of the 21st century, particularly in complex developing countries. This edition also contains a new chapter on competing values and the ethics of public policy. Among other issues, it addresses the intractable problems of corruption and nepotism that are endemic to any policy system. Each chapter also includes references to the latest published South African and international resources on various aspects of public policy. Improving public policy for good governance is essential reading material for all students, researchers and practitioners in the field of public policy who require knowledge, insight and/or practical skills in this important field. All contributors are experienced public policy educators, practitioners and evaluators."--Back cover.
Download or read book Technology Transfer and Economic Development written by Robert G. Hawkins and published by JAI Press(NY). This book was released on 1981 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: Essays on the impact of technology transfer on economic development - discusses definitional issues, transfer channels and forms, the theoretical background, impact of multinational enterprise research and development activities, licensing as an alternative to foreign investment, related economic integration in Western Europe, impact on economic growth in Japan, transfer between the USA and planned economies, efforts at regulation, costs and benefits, etc. References and statistical tables.
Download or read book World Science Report 1998 written by Unesco and published by UNESCO Principal Regional Office for Asia & the Pacific. This book was released on 1998 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: This year's edition of the World Science Report examines the role played by science in resolving the major issues facing human society, such as food security, water resources and disease.
Download or read book Apartheid and the Making of a Black Psychologist written by N. C. Manganyi and published by . This book was released on 2016 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This intriguing memoir details in a quiet and restrained manner what it meant to be a committed black intellectual activist during the apartheid years and beyond. Few autobiographies exploring the 'life of the mind' and the 'history of ideas' have come out of South Africa, and N Chabani Manganyi's reflections on a life engaged with ideas, the psychological and philosophical workings of the mind and the act of writing are a refreshing addition to the genre of life writing. Starting with his rural upbringing in Mavambe in Limpopo province in the 1940s, Manganyi's life story unfolds at a gentle pace, tracing the twists and turns of his journey from humble beginnings to Yale University in the USA. The author details his work as a clinical practitioner and researcher, as a biographer, as an expert witness in defence of opponents of the apartheid regime and, finally, as a leading educationist in Mandela's Cabinet and in the South African academy. Apartheid and the Making of a Black Psychologist is a book about relationships and the fruits of intellectual and creative labour. In it, Manganyi describes how he used his skills as a clinical psychologist to explore lives both those of the subjects of his biographies and those of the accused for whom he testified in mitigation; his aim always to find a higher purpose and a higher self."--Publisher description.
Download or read book Essentials of Conservation Biology written by Richard B. Primack and published by Sinauer. This book was released on 2014-06-26 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Essentials of Conservation Biology has established itself as an engrossing book from which to learn or teach. Combining theory and research and with examples from current literature, the book explain the links between conservation biology and other fields such as ecology, climate change, environmental economics, sustainable development and more.
