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1.
Nimmi Sharma 《Resonance》2011,16(1):38-46
Laser radar, also called lidar, is proving to be a powerful technique for helping us to understand the world in which we live. It can provide information on topography, vegetation canopies, and on characteristics of Earth’s atmosphere. This article describes how laser light scattering can be used in lidar systems to help visualize the structure of our atmosphere and to address a wide variety of important scientific questions from air pollution to climate issues. The article focuses on two specific examples of ground-based elastic lidar, the Micro Pulse Lidar System and the CLidar system, to provide an introduction to the methods of atmospheric lidar measurements and their applications.  相似文献   

2.
Chunks of stony materials dashing into the Earth’s atmosphere evoke awesome moments of fascination. Laymen generally interpret these dazzling displays of nature as ‘meteors’. In this article, various aspects of astronomical and atmospheric meteors are discussed.  相似文献   

3.
Electromagnetic radiation is all around us, and essential for the survival of all lifeforms. It provides valuable information about the physical world around us, feeds us by providing energy to plants, allows us to maintain human metabolism, and cures us of various diseases. This article deals with the various properties of electromagnetic radiation, its sources and detectors, its nature, and its uses. A brief discussion on the absorption spectrum of the Earth’s atmosphere and the atmospheric windows, and celestial objects seen through optical and radio telescopes is also provided.  相似文献   

4.
Increase in the concentration of several greenhouse gases in the atmosphere during the last few decades has warmed up the atmosphere, a phenomena popularly known as ‘global warming’. There are people who believe that ‘global warming’ does not exist, or will have negligible consequences on the earth and its biosphere, if at all it exists. Satellite record over the past few decades have shown a slight cooling trend in the lower troposphere, casting a doubt on the existence of ‘global warming’. During the same time, atmosphere near earth’s surface has shown a warming trend. Efforts are on to explain this temperature anomaly and it may take time to say conclusively whether ‘global warming’ exists or not.  相似文献   

5.
This paper reports on a study conducted among Greek kindergarten teachers aiming to explore their conceptual frameworks on a major environmental issue of our times: the ozone layer depletion. The choice of this particular issue was premised on its novelty, complexity and abstractness which present teachers with difficulties in its teaching. A free word association task was employed to identify the associative meaning of the issue among the participant teachers. The study’s results revealed the existence of a simplistic, linear, cause-and-effect scheme in the teachers’ conceptual frameworks, the two poles of which are “solar radiation” and “its harmful results for human health”. Some of the well-known misconceptions and misunderstandings already emerged in previous research also arise in this study. Prominent among them are the deeply rooted confusion between the “ozone hole” and “greenhouse effect”, a general fusion of ideas concerning all environmental problems and an overemphasis on the harmful consequences of the ozone depletion on human health. Implications for kindergarten teacher education are also discussed.The present study is part of a research project that is co-funded by the European Social Fund and National Resources – (EPEAEK II) PYTHAGORAS II.  相似文献   

6.
A world-class university in China? The case of Tsinghua   总被引：1，自引：0，他引：1  
Yang  Rui  Welch  Anthony 《Higher Education》2012,63(5):645-666
Higher education, an integral part of China’s nation-building project, is a critical element in China’s strategic policy initiative of building national strength through science and education. One way to achieve this goal is to develop a higher education system of international stature. Perhaps more than any other country, through national programs such as 211 and 985, China has been explicit in selecting its best universities for intensive investment, with the expressed aim of making them world-class within coming decades, and contributing more to overall R&D and scientific development. Analysing how these top-tier universities in China are reaching for the gold standard, and using Tsinghua University as an example, this article examines the role of higher education in China’s rise and how Chinese universities are responding to the drive for innovation, against a background of globalisation and internationalisation. It analyses the experience of Tsinghua, a Chinese flagship university, sometimes dubbed ‘China’s MIT’, through an in-depth case study in an international context, seeking to answer the question of how far Tinsghua embodies the qualities of a world-class university.  相似文献   

7.
臭氧层问题以及围绕此达成的蒙特利尔议定书是上个世纪80年代国际环境合作治理重大事件,美国关于臭氧层问题的政策是美国环境外交的重点。无论是臭氧层保护的国际协商,还是最终签署的蒙特利尔议定书,美国是在反环境形象的里根总统任期内实现的。探究里根政府的臭氧环境外交,有助于把握上个世纪80年代美国环境外交的特征和基本走向。  相似文献   

8.
Understanding of Earth’s systems, including the crucial role of human beings within them, is an important part of citizens’ ability to think intelligently and critically about the environment, pollution, sustainability and other socio-economic and scientific issues central to life in the modern world. Part of this understanding involves seeing the world as an integrated whole in which what happens in diverse places in the world may be equally relevant for students' lives. In this regard, it makes sense to study both remote and local environments within the system thinking approach—where such distinctions naturally become blurred. The present research, accordingly, focuses on a study unit entitled “Life at the Poles” and investigates the development of junior high school students’ understanding of Earth systems and their level of conceptual complexity as a result of participating in it. The “Life at the Poles” unit is based on the “explanatory story” approach where one central theme is used as a focal point for an interdisciplinary study of certain natural phenomena, in this case, the possibility of life under the extreme conditions at the poles. Concept maps and Likert-type questionnaires were employed as research tools, allowing the collected data to be analyzed both qualitatively and quantitatively. The research findings indicate that the students significantly improved their Earth systems understanding and, importantly, greatly increased their awareness of human beings’ influence on the environment, including remote environments such as the pole.  相似文献   

9.
Cosmic rays are very high energy particles arriving from the depths of space and incident on the earth’s atmosphere at all places and at all times. The energy of these particles extends over 12 decades from around 109 ev to 1021 ev and mercifully for the survival of life, the intensity falls by atleast 22 decades from about 100 particles/cm2/s to 1 particle/1000 km2 year. Cosmic ray research led to the discovery of many of the fundamental particles of nature in the 30’s, 40’s and 50’s of this century and ushered in the era of ‘elementary particle physics’ at man-made accelerators. Even 86 years after the discovery, the sources of these particles and the mechanism of acceleration continue to remain a mystery.  相似文献   

10.
One of the most important topics on the international agenda in educational research is to gain an understanding of the processes of educational change in teachers and of the factors that favour or hinder it. Such understanding is, for instance, an essential element in planning and putting into practice initial and ongoing teacher education programs. This article reviews the research on science teachers’ educational change. To organize the information, an analogy is made with the process of scientific change, analyzing and evaluating the contributions of the different models taken from the philosophy of science – positivism, Popper’s principle of falsifiability, Lakatos’ scientific research programs, Laudan’s research traditions, Toulmin’s evolutionism, and Kuhn’s relativism. We conclude the article with the implications for science teacher education.  相似文献   

11.
For the last two decades science education researchers have had a major interest in identifying students’ intuitive understanding of a wide range of scientific topics and in reducing the difficulties involved when an attempt is made to replace these views by scientific understanding. Different approaches to this latter problem have been adopted by researchers, with strategies ranging from the pragmatic and atheoretical to those with a stronger theoretical foundation, usually based on some form of constructivism. In this paper we report on a novel theoretical perspective which takes as its foundation the psychological research of about three decades ago which investigated “forgetting,” and the important effects of previous knowledge in this process. In particular this new perspective demonstrates that, under normal teaching conditions, and through the process of proactive inhibition, the student’s prior knowledge can accelerate the forgetting of the newly taught scientific ideas. The paper first develops the theoretical position and then shows that a change in teaching approach can take advantage of the differences between the students’ prior understanding and the scientific view to ensure more efficient replacement. Following this an overview of the new methodology, as it is currently being used on a trial basis by science teachers in South Australia, is briefly introduced.  相似文献   

12.
The ‘Balance of Nature’ metaphor is a pervasive idea in ecology. However, the scientific community acknowledged during the last decades that equilibrium conditions are rare, while disturbance events are not uncommon. We suggest that the exclusive teaching of the ‘Balance of Nature’ metaphor produces cultural, scientific and learning misconceptions about the structure and function of nature. We outline an exemplary educational intervention for high school students to exhibit that the use of computer simulations could serve important educational goals in ecology and environmental education, such as the liberation of the concept of ‘balance’ of its metaphysic burden, the comprehension of the dynamics and the systemic nature of ecological processes and the appreciation of the mutual relation between society and nature.  相似文献   

13.
The world’s three million cross-border international students are located in a ‘gray zone’ of regulation with incomplete human rights, security and capabilities. Like other mobile persons such as short-term business and labour entrants, and refugees, students located on foreign soil do not enjoy the same protections and entitlements as do citizens. International students are affected by two different national regulatory regimes, in the nations of citizenship and of education. But they are fully covered by neither. Their position is vulnerable and uncertain, mediated by non-citizen status and the related facts of cultural difference, information asymmetry and communication difficulties. Referring to research on international education in Australia, which has the world’s fifth largest international student population, the article focuses on the manner in which the subordinated outsider status of international students magnifies the problems they face. It considers what might be done to enable them to access comprehensive protections, empowerment and human rights as defined in the United Nations’ Universal Declaration of Human Rights.  相似文献   

14.
This paper explores the role of the Canadian federal government in two foreign policy areas: overseas development assistance and international cultural relations by providing a brief history of the federal government’s engagement in both policy areas and highlighting the contributions and challenges of Canadian foreign policy to the internationalization of Canadian higher education. More broadly, the paper explores the unique characteristics of the Canadian federal government’s role in higher education policy making, and in particular, its relations with academics and the university community. Ironically in a world increasingly characterized by greater international education flows, in Canada, there has been a narrowing of vision, a focus on more short rather than long term objectives and a limited engagement of dialogue between academics and the government to promote both development assistance and international education as Canada’s soft power.  相似文献   

15.
In their treatise, Mitchell and Mueller extend David Orr’s notions of ecological literacy (2005) to include biophilia (Wilson 1984) and ecojustice (Mueller 2009). In his writings, David Orr claims that the US is in an “ecological crisis” and that this stems from a crisis of education. The authors outline Orr’s theory of ecological literacy as a lens to understand Earth’s ecology in view of long-term survival. In their philosophical analysis of Orr’s theory, Mitchell and Mueller argue that we move beyond the “shock doctrine” perspective of environmental crisis. By extending Orr’s concept of ecological literacy to include biophilia and ecojustice, and by recognizing the importance of experience-in-learning, the authors envision science education as a means to incorporate values and morals within a sustainable ideology of educational reform. Through this forum, I reflect on the doxastic logic and certain moral and social epistemological concepts that may subsequently impact student understanding of ecojustice, biophilia, and moral education. In addition, I assert the need to examine myriad complexities of assisting learners to become ecologically literate at the conceptual and procedural level (Bybee in Achieving scientific literacy: from purposes to practices, Heinemann Educational Books, Portsmouth, 1997), including what Kegan (In over our heads: the mental demands of modern life, Harvard University Press, Cambridge, 1994) refers to as “Third Order” and “Fourth Order” thinking: notions of meaning-construction or meaning-organizational capacity to understand good stewardship of the Earth’s environment. Learners who are still in the process of developing reflective and metacognitive skills “cannot have internal conversation about what is actual versus what is possible, because no ‘self’ is yet organized that can put these two categories together” (p. 34). Mitchell and Mueller indicate that middle school learners should undergo a transformation in order to reflect critically about the environment with a view toward determining critical truths about the world. However, if this audience lacks “selective, interpretive, executive, construing capacities” (Kegan in In over our heads: The mental demands of modern life, 1994, p. 29), assimilating the notions of ecojustice and biophia may be problematic.  相似文献   

16.
Investigation involving children’s understandings of scientific concepts have been a dominant area of research in science education over the last 2 1/2 decades. One fruitful outcome of these studies is to alert teachers to difficulties in learning science. Although this information is commendable in highlighting their existence, not much is presented on how to deal with the alternative conceptions. It is generally believed that teachers tend to teach the way they were taught, and breaking this cycle requires different emphasis on pedagogy in teacher education. The focus of this article is on preservice teachers’ experiences in a science education course as they explore the importance of children’s alternative conceptions and in using such knowledge to make decisions about teaching.  相似文献   

17.
This is a documentary study of education abroad policy in the People’s Republic of China (PRC) between 1978 and 2009. By examining the dynamics underpinning the PRC state’s efforts to shape the flow of Chinese students and scholars from and into China, this article reveals the major strategies that have enabled education abroad to become a source of brain gain. It argues that China’s brain gain strategies feature three characteristics: a proactive diplomatic approach to international educational relations; strategic dependence on foreign higher education resources and a decentralized economic mechanism to raise foreign-trained human capital. The paper concludes by discussing the implications of Chinese experience for our understanding of the complex and dynamic relations between the state, the market, universities and international relations as relating to cross-border academic mobility, international educational relations, and national development in a globalizing world.  相似文献   

18.
Students’ learning interests and attitudes toward science have both been studied for decades. However, the connection between them with students’ life experiences about science and technology has not been addressed much. The purpose of this study is to investigate students’ learning interests and life experiences about science and technology, and also their attitudes toward technology. A total of 942 urban ninth graders in Taiwan were invited to participate in this study. A Likert scale questionnaire, which was developed from an international project, ROSE, was adapted to collect students’ ideas. The results indicated that boys showed higher learning interests in sustainability issues and scientific topics than girls. However, girls recalled more life experiences about science and technology in life than boys. The data also presented high values of Pearson correlation about learning interests and life experiences related to science and technology, and in the perspective on attitudes towards technology. Ways to promote girls’ learning interests about science and technology and the implications of teaching and research are discussed as well.  相似文献   

19.
Earth’s atmosphere is a dynamic system and is driven by numerous interacting factors, which are yet to be studied with precision. Computer models, which are generally run under CO2 doubling scenario, may have uncertainties for several reasons. At the present CO2 emission rate, doubling may be attained only after 70–95 years (at 1% increase yr-1). Global efforts to cut back on CO2 emission, underway for quite sometime, and the stress on the use of alternative non-conventional and renewable energies may increase the doubling time considerably. Nevertheless, the considerable improvements in the capability of ocean-atmosphere models in simulating present climates show that the intricate interplay of several factors in climatic change are now better understood and there is hope for further improvement in the model performance.  相似文献   

20.
This study investigated the relationship between family factors and students’ scientific literacy performance in Hong Kong, which has excelled in science performance in previous international studies. Data were obtained from the 2006 Programme for International Student Assessment. Multilevel analysis was used to examine the relationship between parental involvement and investment and students’ scientific literacy performance. It was found that students’ scientific literacy performance, which was measured by their science achievement and self-efficacy towards science, were significantly associated with certain types of parental investment and involvement even after controlling background factors of both students and schools. Parental investment in cultural resources and parental involvement in terms of organising science learning enrichment activities at an early age were found to be significantly associated with students’ scientific literacy performance. Activities that could be provided at an early age (e.g. watching TV programmes about science, reading books on scientific discovery, watching, reading or listening to science fictions) were found to be highly effective activities for promoting children’s science achievement and self-efficacy.  相似文献   

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