The Impact of New
Technologies on Remote Sensing Education The need for Education in Remote
SensingKurt T. Rudahl and Sally E. Goldin (USA) Goldin-Rudahl Systems Inc. 6 University Drive #213, Amherst, MA, USA E-mail : 0003086210@mcimail.com Here at the 15th Asian Conference on Remote Sensing, one hardly needs two argue the importance of education in remote sensing and related disciplines. The conference program has included session on educational topics since its early years. Many conference attendees are actively involved in education or training, either in formal academic programs or in applied, professionally oriented settings. In fact, the importance of effective wide, spread education concerning remote sensing and related topics had never been greater. This is primarily due to two factors: the multi faceted environmental degradation currently threatening the earth and its people, and the economic significance to each country of intelligently monitoring and administering their natural resources. Few people dispute that the plane is or soon will be in a state of environmental crisis. Pollution, population growth exceeding the support capability of the land, loss of biodiversity and global climate change are only few of the problems that face today’s and tomorrow’s generations. Remote sensing and related technologies can contribute to our understanding of these problems as well as tot eh implementation of practical solutions. Meanwhile countries are becoming increasingly aware that long term economic viability requires a balanced, informed strategy for the exploitation of natural resources forecasting agricultural yields, and developing new energy sources. In order to meet these challenges, we need professional who are familiar with the capabilities and limitations of the geospatial technologies. This includes researchers who can develop new methodologies and applications, as well as technicians and practitioners who can apply proven techniques to specify problems. Even as our need for trained personnel increases, the technological bases for these disciplines have also been expanding rapidly. Remote sensing began such as visual interpretation of aerial photography. Although significant time and training were required to become a skilled photo interpreter, the instruments and tools involved were for the most part accessible and familiar. Today, visual interpretation skills are still important but to extract the vast amount of information contained in modern remotely sensed data, an array of other knowledge is needed: knowledge of the characteristics, advantages and limitations of the characteristics, advantages and limitations of the many different data sources available; familiarity with digital image processing techniques and algorithms; basic competence in mathematics and statistical analysis; at least some knowledge of computer hardware and software; and of course and understanding of the physical or biological processes under examination. Even the letter has become more complex, as we find an increasing need to understand interactions among natural processes and systems, rather than isolated phenomena. Thus, it is more important than ever that remote sensing educational programs provide an adequate exposure to modern technologies, as well as solid grounding in remote sensing theory and principles. Traditional Obstacles In the Author’s ten years of involvement with remote sensing education, we have seen many changes and improvements. Until recently, however, efforts to provide comprehensive education or training in remote sensing faced a variety of serious obstacles:
None of these problems has disappeared. During the last few years, however, there have been developments in the computer industry and in the remote sensing / GIS community that are beginning to have a significant positive impact, and which we expect to become even more important in the future. Table 1 Problem: Need affordable, adequately-powerful hardware New Solutions: Problem: Need accessible, educationally-appropriate siftware New Solutions Problem: Need affordable digital imagery & ways to manage it. New Solutions: Problem: Need to justify and fund remote sensing New Solutions: In the sections that follow, we examine each of these developments in more detail, clarifying how each can make remote sensing education more effective. The Incredibly Cheap PC Most readers are aware that remarkably powerful micrometer hardware is now available at very low prices and we do not wish to belabor this point. However, many may not have considered the specific implications of these market facts for education. Assuming a fixed budget for purchasing a computer (and ignoring the influence of inflation). A small computer such as the 1986 model shows, provided adequate resources for book keeping and work processing. The early versions of our DRAGON/ips software demonstrated that a computer of this type could even be used for some aspects of remote sensing education. However, realistic remote sensing analyses on data sets significant demand on a computer’s speed, memory and storage capacities, and graphical display.
Although the 1994 model does not show a qualitative change from earlier available hardware, the quantitative changes are such as to change impractical tasks to simple ones. Two of many possible examples will suffice :
At the same time that basic computer hardware has fallen price, peripherals important for remote sensing have also become significantly more available. The primary categories include hardcopy input devices color printers, and the range of CD ROM technology which is only beginning to be explored. Another area where more affordable hardware impacts remote sensing education is portable computing. Today’s laptop and notebook computers are sufficiently powerful, portable, and robust, that doing image processing in the field as become quite practical. While a portable computer may be as such as 1005 more expensive than an equivalent desktop configuration, process are still well within the range of many educational organizations, particularly since one or two units will usually suffice. Finally, the expansion of low cost computer technology, particularly in the are of graphics has had a side effect which is potentially very useful for remote sensing educators : the proliferation of computer graphics/desktop publishing service bureaus in may urban areas. These commercial enterprises can provide high quality output at reasonable cost, for presentation and publication. This removes the need for educational organizations to purchase expensive hardcopy output devices; the money saved can instead be invested in a larger number of student workstations, in software, or in data. While these service bureaus may not yet be available in all locations, they are rapidly growing economic sector which should be attractive to entrepreneurs in almost every major city.
The Software Revolution Eight years ago the Asian Institute of Technology, at the forefront of remote sensing education in the Asia Pacific region, had a variety of image processing software, ranging from mainframe to PC.
With these software resources (which were generous for that period), we typically spent two thirds of the time allotted to digital analysis laboratory simply teaching the mechanics of using the software. Time available for students to actually do image analysis was correspondingly reduced. Our own DRAGON software was developed partly in response to these conditions. By contrast, the same criteria applied to the current version of DRAGON are shown in Table 5.
Goldin Rudahl systems pioneered the use of standard personal computers for remote sensing analysis, especially for education with DRAGON/ips. The goal was to provide low cost, easy – to – use software on a low cost, readily available hardware platform. Now, seven years later, a number of other companies have followed our lead. The significant point here is that the state of the art has changed dramatically. The level of performance outline above is what a remote sensing educator can and should reasonably expect of a modern remote sensing software package. Internationalization – The Next Step in communication Those who are reading this paper presumably understand English, and it may be supposed that all of your students have to learn one of the major technical languages. Nevertheless, a person is a most always most comfortable using his or her native language, and software which can interact with a student in familiar terms will be easiest to learn. New software methodologies are now coming into use which facilitate the development of internationalized software –software which interacts with the user in a national language of choice. The problems of translation, of finding suitable technical terminology and suitably knowledgeable translators, remain the same. However, correctly designed software can no integrate translated prompts and message with a minimum of effort and without requiring any knowledge of the language by the software developers themselves. Our own newly available Bahasa Malasiya/Bahasa Indonesia version of DRAGON is an example of this process. (we also have a Spanish version; other similar projects are under way) Perhaps even more important than the comfort of the student, however, is the need to communicate analysis results to the non expert : to government officials, funding agencies, and the lay public. Colorful and attractive maps and images are an important part of this, but clear labeling in a language understood by the intended use is crucial to communication. Especially here in Asia, this labeling involves not only the correct words but also use of the correct character set (or sets). The apparently simple task of typing the name of a city, to appear as a label on the image, can take on considerable complexity. While easy enough in English, Indonesian, or Swahili, it becomes a bit more difficult with the accented characters in French and Spanish, quite a bit more difficult with alphabetic languages not based on Roman characters, such as Cyrillic, Greek, and Thai, and a major challenge when the character sets number in the thousands of characters. Of course, all these cases must be handled without compromising the simplicity of standard Raman character entry. Recently, a new standard for representation (almost) all the world’s languages has been completed by the International Standards Organization working with the Uniceode Consortium and national groups worldwide (but especially in China, Taiwan, Japan, and Korea). New software, including DRAGON, is beginning to incorporate this ISO-10646/Unicode standard as the basis for a powerful and flexible text display capability (Figure 3). Graphical User Interfaces Most readers are probably familiar with graphical use interfaces (GUIs) such as Microsoft Windows, the Macintosh interace OS/2 Presentation Manager, and X Windows/Motif. AGUI extends the vocabulary available to the software designer for communicating with the user. Simple text messages are augmented by lines showing grouping or flow, small pictures depicting recognizable actions, standardized or conventional symbols, and dynamic displays which respond to user actions. Graphical user interfaces are often hailed as being much easier to learn and use than “old –fashioned” character-based interfaces. When used well by the software designer, a GUI can facilitate the user’s comprehension of “what the software is doing”. When designed inappropriately, a GUI cumulated with proper use of the software, encourage a non-professional video-game approach, or even hide the inadequacy of the software. One negative aspect of GUI is that it almost always requires more powerful hardware to achieve a particular level of performance than does a comparable non-graphical package. While this fact may become less important as hardware costs drop, it is still a consideration in examining options for educational software. Acquiring and Managing Image Data CD-ROM An outgrowth of the audio CD, the CD-ROM may ultimately have as large an impact on history as the invention of printed books. Although less convenient than a book, CD-ROM is much smaller (10 cm3 vs 1200 cm3), contains much more data (6x 108 characters vs 6 x 106), costs much less to manufacture ($1 vs$5 , in large quantities), and has about the same durability. Faced with this dramatic alteration in the economics of data, government agencies and corporations are realizing that it is cheaper and easier to publish their results as a handful of CD-ROM disks than as half a ton of paper-and then to relieve budge pressures by pricing the disks low and selling as many as possible. Thus it is now possible to buy, for US$100 or so per disk, detailed geophysical, climatologically, ecological, demographic, and historical data sets covering an entire country. Vendors of earth satellite data, too, are beginning to use this technology. The data sets themselves are still costly, but CD-ROM data from SPOT Image and EOSAT, for example, can be read on any PC equipped with in inexpensive CD-ROM drive. These developments are particularly significant for remote sensing educatin because they provide direct access to large data sets. Unitl the advent of CD-ROM data distribution, there was no practical or affordable way for educational labs equipped with personal computers to read and process data in the form distributed by vendors. Tape drives were too expensive and complex for most educational environments. Educational users of remote scenting data typically had to find some organization with a mini-commputer and a tape drive, to read their data and subset it into pieces small enough to be transferred to a PC hard disk. This was slow, cumbersome, and error-prone. CD-ROM technology makes it possible for a personal computer user to get fast, immediate access to enormous amounts of image data. Furthermore, CD-ROM, unlike tape, is a random access medium This means that a user can select exactly which bands or sub areas of an image he or she wants to process, and quickly start work on this data. With traditional sequential access media like tape, it might be necessary to read past dozens of megabytes of unwanted data, in order to order to reach and extract a subarea of interest. One of a kind CD-ROMs The newest twist on CD-ROM technology is the ability to create your own. Special equipment is required to produce a CD-ROM, but service bureaus are beginning to appear which do just that, at prices starting as low as US$125 for the first copy and dropping for several or a dozen copies. The advantage, of course, is that these CD’s can be read on any standard CD-ROM drive. It is too early to tell what impact this exciting development will have on remote sensing education, but one can imagine a variety of applications. For instance, regional organizations might publish an atlas of local imagery for use in schools and universities. The results of student projects might be captured on CD-ROM and disseminated to other educational organizations. Image Data from Hardcopy or the Real World Remote sensing is sometimes assumed to mean processing of data from earth-orbiting satellites. However, there are times, when satellite data is too expensive, or too low resolution, or simply unavailable. Aerial photos constitute an inexpensive source of image data which can be digitized and subjected to digital analysis. The spatial resolution of aerial photos is much higher than satellite data and the photos may be available inexpensively from government sources. Alternatively, it may be possible to commission special flights at reasonable cost. Furthermore, aerial photo archives frequently stretch back much further into history than satellite image archives. This makes aerial photography particularly useful for multitemporal work. Color-Infrared photos even provide some multi-spectral information. One problem in working with aerial photography is the fact the high spatial resolutioin can overwhelm processing capabilities when working with a large area. Photographs can be successfully scanned at quite high resolution, but the resulting images scan be much larger than can be viewed or conveniently processed. Other technologies exist for capturing images of the real world directly, without going through a hardcopy photography phase.
Remote Sensing Education – Communicating the Need Remote sensing is not an end in itself. It is a tool a very powerful one for understanding and hopefully improving our natural and social environments. To those of us here at ACRS, this is self-evident. To the government ministers and officers who control our budgets and implement politics, helpful or otherwise, it is not at all self-evident. Nor should it be: their function is to require that we demonstrate the value of remote sensing and remote sensing education. Remote sensing technology is not very accessible to the lay person. Necessar foundation concepts such as electromagnetic radiation, multispectal analysis, orbital paths, and so on, are difficult and unfamiliar. Further more, it is not easy to relate the highly technical field of remote sensing to real-world problems like hunger, disease, and urban crowding. Yet, we need to make these connections in the minds of decision-makers, if we are to ensure ongoing support for education in remote sensing and associated technologies. Recently, the most ubiquitous technology of our era, television, has provided some assistance in communicating the potential importance of remote sensing. Educational and news programs have started to use remotely-sensed images to help viewers visualize phenomena at a regional scale. For example, a widely-publicized image of the Rodonia region in Brazil shows more dramatically than any characteristics the extensive damage being inflicted on the Amazon rainforests. In most cases, television viewers are probably not aware of the source of these images. However, this type of usage makes the general public and the decision-making community more familiar with the products and applications of remote sensing can do, and why it is important. The expanding use of Geographic Information Systems can also help to justify support for remote sensing. Increasingly, appropriately or not, remote sensing is being seen as a component or sub area of GIS. Possibly it is easier to explain geographic analysis to a layperson in GIS terms, by focusing on the analogies to conventional maps. Sine most people are at least somewhat familiar with thematic maps, it should be fairly straightforward to illustrate how GIS can be used to understand environmental and social problems. Thus, to increase support for remote sensing education, we should be explicitly broadening our educational objectives to include other aspects of spatial will make it easier to communicate the need for educational programes to governments, funding agencies and the general public. At the same time, revising our definitions in this manner will allow us to provide students and trainees with remote sensing education broader, deeper, and much more relevant to the world’s problems, than what we have offered in the past. We, the technical experts, need to recognize the importance of educating the general public about these technologies for the sake of society as well as to ensure support for formal educational programs. Geographic knowledge and environmental awareness are essential for citizens making decisions n today’s global society. Although discussions of remote sensing education have typically focused on programs at the university level and above, we are beginning to see efforts at the secondary and even the primary school level. It is particularly critical at this time to focus on remote sensing education in the so-called less developed countries. Remote sensing is a discipline which was originally sponsored by a few large industrialized countries. Now, however, foreign aid is becoming unreliable due to worldwide financial inhabit, and developing countries re beginning to question the motives of externally sponsored aid projects. At the same time, developing countries have the most to lose from environmental crises and mismanagement of their national resources. Therefore, remote sensing must become a respected and economically viable activity within each individual country. Policy advice based on remotely sensed data must originate from and be supported by local expertise, locally educated. Conclusions The task of providing realistic, relevant education in remote sensing has become less difficult, due to the technological trends highlighted in this paper. Adequate funding and in fracture remain a problem, but given even a modest budget, it is now feasible to offer training programs that are more comprehensive and advanced than anything we might have imagined a decade ago. Increased public comprehension and awareness of the methods and purposes of remote sensing is seen as a key to public support, while attention to maintaining connections to related disciplines may guarantee a continuing demand for the products of remote sensing. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||