From Teachers Centered To Students Centered Engineering Education

Transformation: From teacher-centered to studentcentered engineering education Journal of Engineering Education, Jan 1999 by Catalano, George D, Catalano, Karen We compare and contrast teacher-centered and student-centered paradigms of engineering education. We identify the following seven roles for teachers wishing to adopt a studentcentered paradigm: 1) model thinking/processing skills, 2) identify students' cognitive development, 3) develop questions that facilitate exploration/growth, 4) introduce visual tools to aid establishing connections, 5) provide group learning settings, 6) use analogies and metaphors, and 7) provide a "no-risk" student feedback channel for information. Several case studies for different subjects and from different institutions are presented. Our results indicate a student-centered model is most effective when coupled with academic depth and experience in the subject matter.

I. INTRODUCTION At a recent federal services academies conference, Cross' delivered a keynote address which challenged the assembled audience of instructors to develop an environment in which students become "actively engaged." Decades of research focused upon teaching and learning strategies has documented the effectiveness of an "active learning" model. Administrators at institutions of higher learning are challenging their respective faculties to incorporate this relatively new model into their classrooms. While some faculty have embraced active learning with enthusiasm, others remain more cautious. Engineering education efforts both in design and in the engineering sciences have been reported.2-5 We seek to add texture to the movement towards active learning, though opting for a slightly different terminology. In a "student-centered" approach to education, the student is at the center of attention while in the more traditional or "teacher-centered" model, the teacher is the focus. Active learning is more likely to occur in the student-centered model while passive learning is more likely to result in a teacher-centered model. Shifting the center of attention of classroom activities from the teacher to the student metaphorically seems to us to be a significant paradigm shift in education. Whether or not such a shift is "revolutionary," recalling the historical origin of that word from the late Middle Ages, perhaps depends on the stubborn resistance that a teacher may encounter in attempting to make such a change.6 In the present work, we shall compare and contrast a studentcentered approach to education to a teacher-centered approach. We shall provide and discuss the following list of specific roles for teachers who wish to explore a transformation of their own classrooms: * model thinking/processing skills * identify students' cognitive development * develop questions that facilitate exploration/growth * introduce visual tools to aid establishing connections * provide group learning settings *use analogies and metaphors

provide a "no-risk" student feedback channel for information. Our particular transformation has taken place in engineering design courses and engineering science courses taught at both Louisiana State University (LSU) and the United States Military Academy (USMA). We have attempted to assess the effectiveness of our transformation at both institutions and make some comparisons as well. II. CHANGING MODELS OF EDUCATION According to Halperin,' most activities today in a vast majority of classrooms continue to reflect the older teacher-centered model of education wherein "students sit quietly, passively receiving words of wisdom being professed by the lone instructor in front of the class." Bowers and Flinders8 describe a variation of the teacher-centered model, teacher as "classroom manager," in which the learning process is likened to industrial production, within which students become "products," behaviors are expressions of "exit skills," "competencies," and "outcomes." Implicit in this model that dates to the Industrial Revolution9 are the following assumptions: * any and all educational processes are culturally neutral, linear and rational * language serves as a non-filtering conduit for the transmission of information * the learning process is heavily dependent upon the pronouncement and the enforcement of rules. Note that little is required or expected from the student until the very end or "final quality control inspection." In this model, the student simply rides the assembly line of learning, quietly and dutifully accepting all inputs as does a skeletal frame on an automobile manufacturing plant's assembly line. A modern day, high technology version of the same model of education has been described by Capra.lo According to cognitive psychologists and educators, instruction is most effective when students are encouraged and even expected to become actively involved in their own learning, thereby shifting the focus from what the teacher does to what the students do. King" asserts that key to the learning process is what the teacher actually asks the students to do with the subject matter that is being studied. Open-ended interactions between teacher and students and student groups nurture the student's natural curiosity. Many concepts may not be subject to precise definitions but may be more richly described through the use of both examples and analogies.l2 Cooper et al.'3 sought to promote student activity through the use of cooperative learning experiences including peer tutoring, student-faculty research projects, short term "buzz" groups, and learning communities. In engineering education, extensive work on active learning has been reported by Feldert4 and Smith.ls During the review process for this work, additional works by Felder were identified as referenced in his homepage (http://www.ncsu.edu/faculty/rmf2.html). Felder" has identified the following six principles for good teaching * write comprehensive instructional objectives * model strategies and skills for your students * maximize experiential learning and minimize lecturing * use team-based learning extensively * do not make speed a factor on tests * positively reinforce successful performance. Houshmand et al." developed a total quality management approach in which administrators, faculty, and students work together to develop a methodology for improving the actual learning that takes

place in the classroom. Others have incorporated "hands-on" experiences ranging from the use of multi-medial' to the entry into collegiate design competitions.l8 A PROFESSOR'S ROLES IN STUDENT-CENTERED EDUCATION From our review of the literature and from our experiences in undergraduate education, we suggest the following seven roles for a professor who wishes to explore a transformation from teachercentered to student-centered engineering education. A. Model Thinking and Processing Skills One of the most important actions a teacher can take is to think out loud or externally process. A student-centered teacher may model brainstorming or problem solving. Students cannot read our minds nor do they have any idea about our struggles as learners unless we choose to share this information with them. Rather than a soliloquy, students are better served by frequent and revealing "streams of consciousness" with allowances for repeated interactions between the teacher and the students. Haddock"9 eloquently describes such sharing as being a "nurturing professor." We offer a more colloquial and anthropomorphic metaphor, teacher as "border-collie," shepherding students along a path yet keeping a distance, constantly in motion yet never at the center of attention, ever vigilant yet never dominant. Example: Fluid Flow Exiting a Large Reservoir through a Small Orifice Student-Centered Professor's Verbalized Inner Dialog: "Which conservation laws are at work here? Why should I use the conservation of energy? Why shouldn't I use Navier-Stokes? Is Mach number important? Is Reynolds number important? Should I consider the flow laminar or turbulent? Viscous or inviscid? Compressible or incompressible? 1-D, 2-D, or 3-D?" B. Know the Actual and the Desired Cognitive Levels of Activities and of Students Two models of thinking that we find useful both from a teacher's perspective and for generating discussion with our students are Bloom's taxonomy" and Guilford's structure of the intellect.2" In Bloom's model, thinking proceeds from the lowest level, rote memorization, to the highest levels, synthesis and evaluation. Guilford's model, as described by Aschner and Gallagher,' divides thinking into memorization or simple recall, convergent thinking which requires the use of data to arrive at a response, and divergent thinking which calls for the generation of alternatives and evaluation which requires judgments and decisions to be made. Our standard practice in developing quizzes, assignments, design projects and tests is to identify the required thinking level and type using both Bloom's and Guilford's models. More than simply for our use, we routinely engage students in identifying the modes of thinking required in the different activities and possible reasons for difficulties they may have had. The following describes levels of thinking adapted from reference 20. Level 1: Recognizing Level 2: Memorizing Level 3: Translating Level 4: Making connections Level 5: Solving problems Level 6: Breaking down barriers Level 7: Fitting pieces together Level 8: Drawing conclusions

Level 9: Evaluating pros and cons Example: Importance of Reynolds number Increasing Levels of Thinking: * Recognize Re as the Reynolds number. * Calculate Re for a given flow through a circular pipe. * Calculate the friction losses for given flow through a circular pipe. * Design an experiment that demonstrates the relationship of friction losses to the Reynolds number for flow through a circular pipe. C. Develop Questions that Facilitate Student Exploration and Growth. Questioning techniques and their importance in shifting the focus to the students are reviewed by Hansen,3 Dantonio,24 Taba,5 and Ehrenburg and Ehrenburg.zb Each provides a general framework to describe the questioning process, identifying four distinct categories: * information gathering * information sorting * information organization * information interpretation. Information gathering refers to the data collection process while information sorting refers to a process much like the sorting process that occurs in a mailroom. After a brief discussion on the types of questions, we provide to our students concrete examples from the different categories. Throughout the rest of the semester, students are asked to generate their own questions both in class and as homework assignments and fit them into the framework already provided insuring that questions from each of the four categories are included. Example: Using the Second Law of Thermodynamics Student Homework Assignment: Suppose hunger strikes and you decide to hard-boil several eggs in a kettle of water. * Recognize the physical properties of the water and the eggs you will need to estimate. * How much heat is needed to finish the hard-boiling process? * Is the process reversible for the eggs? The water? Why or why not? D. Use Visual Tools to Establish Connections and Nurture the Development of These Tools in Students Research into whole brain thinking suggests the brain's left hemisphere is associated with linear, analytical thought and the right hemisphere dedicated to spatial, integrative thought.27 The teachercentered model of education essentially ignores one half of the student's mental capacity. A visual tool we have found useful in tapping into that neglected portion of the brain is mindmapping.zs From the outset, the emphasis is placed upon the process of constructing the map-not the final product itself. Mindmap construction forces students to sort through new information and cluster the data into categories that indicate the existence or lack of connections. Mindmaps can be used throughout the semester both for the introduction and overview of new material and as a review mechanism for establishing the connections among old pieces of information. An example of a mindmap used during the first meeting of fluid mechanics is provided (Figure 1). In addition, advances in classroom technology offers an entirely new set of visual tools. State-of-the-art presentation graphics will soon become an essential component of a studentcentered classroom environment .29 Even at this embryonic stage of technical refinement, studentcentered classrooms as found in studio and partial studio models have been developed and are being offered in courses (i.e. heat transfer, thermodynamics) traditionally reserved for the teacher-

centered approach.30 We have used the graphics available from commercially available symbolic software packages in engineering mathematics and found them to be effective in the presentation of concepts in analytical geometry. We have also used such graphics packages in our introduction of the science of chaos into fluid mechanics. E. Provide Group Learning Settings. Cooper et al.31 provide critical features for group learning: positive interdependence, individual accountability, appropriateness of the assignment, teacher as facilitator, explicit attention to social skills, and an emphasis on face-to-face problem solving. Three tests of actual involvement of the students in a group learning environment, offered by Weimer,32 include the amount of actual class time that is actually dedicated to group learning, the number of students who participate, and the depth of involvement of the students in the various activities. Two particularly effective group learning activities we have identified for use in the engineering sciences include: 1) construction of teams of two to three students to work out solutions to well-defined and open-ended problems and then present their group results to the rest of the class for review and 2) establishment of studentrun recitation period wherein students ask other students for suggestions and guidance with the instructor serving as an interested observer and facilitator. F. Use Analogies and Metaphors. Eco,33 borrowing from the writings of Dante Allighieri, eloquently describes the power of metaphorical thought, points to its integral part in the arts and humanities, and provides a skeletal framework of categories of meaning moving from the literal to the most interpretative. Eco suggests four levels of meaning: * the literal * the metaphorical * the moral * the anagogical. By anagogical, Eco points to the very highest or ethereal level of interpretation. For example, according to Eco, Dante's description of the Exodus at the literal level refers to the departure of the children of Israel from Egypt, at the metaphorical level it refers to human redemption, at the moral level it refers to the conversion of the soul from darkness to a state of grace, and at the anagogical level to the release of the spirit from the bondage of darkness to the freedom of eternal glory. At this stage, our attempts to move from the literal to the ethereal have been small, cautious steps. Some concepts in the engineering sciences seem ideally suited for a richer description. For example, we have framed an introduction and discussion of the basic conservation laws in terms of the current debate over immigration policies. In thermodynamics, we have likened energy, the availability of energy, and the Second Law to gross income, net income, and the passage of time. Our examples serve as a springboard for our students who are subsequently asked to envisage their own analogies and metaphors and present their work to their peers. Example: The Reynolds Transport Theorem Student Assignment: Recognize the Reynolds transport theorem. Discuss the process of taking a trip to New York City as an analogy for the concepts of path dependent and path independent functions used in thermodynamics. Take West Point as the starting point and the theater district OffBroadway as the final point. G. Provide a "No Risk" Mechanism for Indirect Dialogue Between Professor and Students Our suggestion of a "no risk" mechanism is the "discovery sheet." Discovery sheets seem most appropriate after the introduction of new and particularly difficult material, after quizzes and test or whenever there seems to be sense of frustration or alienation within the class. Statements, though

open-ended, can range from the particularly specific (i.e., "I felt the exam was fair/unfair because....") to the remarkably vague (i.e., "I wish....".) Key to the successful use of discovery sheets is a prompt and complete response to any and all concerns raised. Often the mere expression of acknowledgment by the professor of a student issue transforms the classroom environment from indifference or at its worst, hostility, to a functioning, healthy community. IV. ASSESSMENT We have only considered one aspect of assessment in this work, performance on group hourly and final exams. Certainly there are many other factors that can be included. We sought to focus on two specific issues that are presently the subject of much debate in engineering education: * Given the existence of multiple sections of the same course and the resultant desire/need to impart a specific set of information for those courses are students helped or hurt (relative to their classmates) by a shift to a student-centered approach if that shift varies from section to section? * What is the relationship if any between the effectiveness of student-centered roles and technical depth and experience of the instructor? Experiments have been performed at both Louisiana State University and the United States Military Academy. At Louisiana State, the comparison involved students in introductory fluid mechanics while at the United States Military Academy comparisons involved students enrolled in an equivalent fluid mechanics course as well as thermodynamics. When we refer to using a studentcentered model, our meaning is that each of the seven roles for the student-centered professor is employed. We model thinking and processing skills whenever appropriate but especially after homework or exams are completed. Second, we engage students in a discussion of Bloom's taxonomy and the Guilford model most notably prior to exam dates seeking to help our students identify the kinds of questions they may encounter. Third, we constantly remind students of the different kind of questions and ask them to develop their questioning techniques primarily through requesting them to make up their own credible exams and provide solutions. We introduce students to mindmapping at the beginning of the term and ask them to map each new reading assignment and then revise their maps after the material is covered in class. We also ask students to prepare comprehensive mindmaps in preparation for exams. We routinely break up our classes into smaller teams and ask them to do both inclass and out-of-class assignments as a team. We use as many analogies and metaphors in class discussion as we can imagine and, in turn, ask students to come up with their own metaphors. On a bi-weekly basis, we solicit student response and discussion of their thoughts and feelings through use of the discovery sheet. Details of the LSU experiment are provided in an earlier article.34 Two sections of fluid mechanics, taught by different professors were offered, one using a traditional teacher-centered approach, the other utilizing all of the roles described previously. The students in both sections received the same exams throughout the semester with the grading done without the names of the students or their section identified. The two professors collaborated in the preparation of all exams with each contributing approximately 50%. Three main conclusions were reached in this study. First, the students in the student-centered section did consistently better throughout the semester on the hourly exams and the final exam. Second, fewer students dropped the student-centered course. Third, the teacher who utilized a student-centered technique was judged much more favorably by the students in his class than he had been rated by students previously. More details are provided in reference 34. Much more extensive data is available for the two experiments run at the United States Military Academy. Data from the experiments performed in thermodynamics over two separate semesters are provided first. In the fall semester 1996, eleven sections were offered with three utilizing a student-centered approach, all taught by the same instructor.

During the spring semester, eleven sections were again offered but this time only one studentcentered section was taught. Three one-hour exams were given during the semester along with a comprehensive final exam. The results are shown in figure 2. Some discussion of the ground rules for the comparison/contrast is essential. The student-centered professor had minimal input into the construction of the hourly exams as well as minimal input into the term end or final exam. Each section during both terms was made up of approximately 18 students (cadets). All exams were identical. The grading was done primarily by the teacher-centered instructors according to a detailed grading sheet. In fact during the spring term, the student-centered professor did not grade any of the test papers. Additionally, the professor who employed the student-centered techniques has a substantial academic and research reputation in fluid mechanics, not thermodynamics. Teacher-centered classroom results are plotted using a solid line while student-centered classrooms results are plotted using a dashed line in figure 2. Several observations can be made. First, the student-centered model does not penalize the students involved even though the tests are made up of teachers utilizing the more traditional approach. Second, the use of the student-centered model does not appear as effective as had been the case at LSU in fluid mechanics. Data are available for fluid mechanics for the fall semester, 1997 at USMA. A total of ten sections of fluid mechanics were offered during the fall 1997 term again with approximately 18 students (cadets) in each section. Only one section employed a student-centered model completely though the other nine sections did employ some of the techniques sporadically. Again the student-centered professor had minimal input into the hourly exams or the final exam and graded less than 10% of the examination problems. The results for fluid mechanics are consistent with observations made at the end of the LSU experiment. The performance of the students (cadets) was stronger for both hourly exams as well as for the final exam (figure 3). Reinforcing a point made earlier, the professor who utilized a studentcentered model has a strong background in fluid mechanics and performs much research in this area. V. DISCUSSION OF RESULTS There are serious shortcomings with the experiments as described in this report. Certainly it would be advisable to have a much larger data sample from more sections over a longer period of time. In addition, it would have been helpful to have the same instructors involved in both the thermodynamics and the fluid mechanics comparisons at USMA. As has been pointed out during the review process, varying backgrounds of instructors can greatly affect student performance and the data are much more valid when the same instructors are used. Having qualified the results, it is our belief that the work suggests but does not prove the following points. We start with the premise that all of us as engineering educators seek to maximize the learning that takes place in our classrooms. Changing from a teacher-centered to a student-centered seems desirable given recent advances in education and learning theory. From our experiments, changing the classroom model does no harm to students even under the constraints imposed by multiple sections and group examinations, certainly an overriding concern for all of us. Some traditionalists still argue that the inclusion of many of the student-centered roles in the classroom will lead to a lessening of the academic rigor of the presentation. Our data both from LSU and USMA seem to contradict this assertion. In order to truly reap the benefits of the student-centered model, however, our results also indicates

that there may be no substitute for depth and experience in the subject matter, a depth that comes from wrestling with the subtleties of the discipline as has been required in the past or is required in the present in ongoing, technical, research efforts. Stated another way, student-centered roles and activities seem most effective when coupled with technical depth, not as a substitute for such expertise. We are not stating that the change to student-centered education should be slowed down or rethought in any substantial way. Rather we are suggesting a precondition for most effective employment, the development of technical depth in the specific subject matter. Though not included in the present work, student evaluations were completed both at LSU and at USMA. At LSU, as has been reported earlier, students in the student-centered section judged their professor's instructional technique, support and effectiveness higher than those in the more traditional section. At USMA, students judged their professor's teaching effectiveness slightly lower in the student-centered sections in thermodynamics but considerably higher in fluid mechanics. Thus, student evaluations at both institutions mirrored the results from normative testing. VI. CLOSING COMMENTS We have identified seven roles for professors seeking to move from the traditional, teacher-centered model of the classroom to a more student-centered approach. Our list does not presume to be complete and all-inclusive; rather it identifies those that we have employed. Many other studentcentered/active learning activities have been employed by other educators, some as simple as learning the names of their students. Attempting such a change is not without resistance from colleagues, from the students themselves and frequently from ourselves. Colleagues will routinely question the academic rigor of such activities and in an often condescending manner ask questions such as *What does that have to do with thermodynamics or fluid mechanics?" Students will often feel very uncomfortable in such a new environment in which they become the center of attention. The proposed change is difficult for many faculty members because it requires relinquishing authoritarian control in the classroom and allowing the intrusion of apparent chaos-thus creating the classic confrontation between order and disorder that has been explored in the West since Aeschylus in Aound35 Student-centered roles take a great deal of time to develop and to implement effectively. The increased workload for instructors and possible economic constraints of the institutions must be included in any discussion of curriculum transformation. Issues related to time seem especially critical, not only the time required for the student-centered roles but also the time required to develop expertise and experience in a specific subject matter.

REFERENCES 1. Cross, P., Keynote Address, Federal Service Academies Conference on Teaching and Learning in the 21st Century, United States Military Academy, West Point, New York, Sept., 1996. 2. Knox, P.C., D.A. Sabatini, RL. Sachs, P.D. Haskens, L.W. Roach, and S.W. Fairbarn, "A Practitioner-Educator Partnership for Teaching Engineering Design,"Journa/aofEngiingEdzon, vol. 84, no.1, Jan., 1995, pp.5-12. 3. Carroll, J., R Fearn, and R Rivers, "Flight Test Engineering-An Integrated Approach," Journal ofnsginertg.Education, vol. 85, no.1, Jan., 1996,pp. 73-76. 4. Crease, R, "A Project Centered Engineering Program." Engineering Educain, 1987 (AUTHOR: PLEASE COMPLETE REFERENCE -WHICH ISSUE?), pp. 100-105.

5. Quinn, R, The E4 Introductory Engineering Test, Design, and Assimilation Laboratory," Engineering Education, 1990 (AUTHOR: PLEASE COMPLETE REFERENCE -- WHICH ISSUE?), pp. 423-425. 6. Capra, F., The Tao ofPhysics, Shambala, Boston, 1975. 7. Halperin, D., Changing College Classrooms Jossey-Bass, San Francisco, 1994, pp. 11-12. 8. Bowers, C., and D. flinders, Responsive Teaching Teachers Colle New York, 1990, pp. 5-14. 9. Mumford, L., Te 10. Capra, F., The WeX of tfe, Anchor Books Doubleday, New York, 1996. 11. King, A., Inquiry as a Tool for Critical Thinking," in Halperin, D., (ed.) Changing College Classrooms, Jossey-Bass, San Francisco, 1994, pp. 13-38. 12. Decyb, B., "Using Examples to Teach Concepts," in Halperin, D., (ed.) Cha,oangrng College Classrooms, JosseyBass, San Francisco, 1994, pp. 39-63. 13. Cooper, J., P. Robinson, M. McKinny, Cooperative Learning and College Ins/raon. Selected Use of Student Learn:ng Teams, CSU Inst. for Teaching and Learning, Long Beach, 1990. 14. Felder, R, "Who Needs These Headaches?", Success?OG, No.4, Fall, 1997. 15. Smith, K., Conversations on Creating a Different Classroom Environment," Proceedings,1997 Frontiers in Education Conference, IEEE, 1997. 16. Houshmand, A-, C. Papadakis, J. McDonough, T. Fowler, and G. Markle, "Methodology for Improving the Quality of Instruction,"Journal of Eng>'eengEducaf*on, vol. 85, no.2, April 1996, pp.117-122. 17. Lamb, A., "Multi-media and the Teaching-Learning Process," in Albright, M., D. Albright, and G. Graf, (eds.), 7earXingin fXe norma*0n JIge, Jossey Bass, San Frandsco,1992, pp. 33-42. 18. Catalano, G. and K. Tonso, "The Sunrayce 95 Idea: Adding Hands-On to an Engineering Curriculum,"Journa/aEngineer uca*on, vol. 85, no.3, July 1996, pp.193-200. 19. Haddock, J., "Profile of a Nurturing College Professor," journal of Engineer>ngEduca*on, vol. 82, no.l,Jan 1993, pp. 34-37. 20. Bloom, B., Taxonomy ofEdvnationaSOoyes, vol. 1, McKay, New York,1956. 21. Guilford from Ascher, M., and J. Gallagher,XSystemfor Classifying Though, Processes in the Context of Taf,erhallnterac'on, University of Illinois Institute for Research on Exceptional Children, Urbana, 1965. 22. Ascher, M., and J. Gallagher, .fl System for Classiing Thought Processes in the Context of Verhal/nteraction, University of Illinois Institute for Research on Exceptional Children, Urbana, 1965. 23. Hansen, C., "Questioning Techniques for the Active Classroom," in Halperin, D., (ed.) Changing Col/ege Classrooms, Jossey-Bass, San Francisco, 1994, pp. 93-106. 24. Dantonio, M., How Can We Create Th.ners? National Education Service: Bloomington, 1990. 25. Taba, H., H:Ida Taha 7eachtng Strateges Program, Institute for Development, Miami, 1978. 26. Ehrenburg, S., and L. Ehrenburg, Buudingandllpilying Strategies for Intellectual Competencies in Students (Basis, Institute for Curriculum and Instruction, Miami, 1978. 27. Williams, L., Tew-Siarlnir*f'ortlre Two-SrrledBrain, Prentice Hall, New Jersey, 1983. 28. Wycoff, J., MAn?dma,psig, Berkeley Books, New York,1991. 29. Head, T., "New Directions in Presentation Graphics," in Albright, M., D. Albright, and G. Graf, (eds.), Teaching in ,he Information -ge, Jossey Bass, San Francisco,1992, pp.17-32. 30. Ribando, R, and G. O'Leary, "Teaching Modules for Heat Transfer," private communication. 31. Cooper, J., P. Robinson, and M. McKinney, "Cooperative Learning in the Classroom," in Halperin, D., (ed.) Changing College Clu.srooms, Jossey-Bass, San Francisco,1994, pp. 74-91. 32. Weimer, M., "Active Learning: Ouantity, Extent, Depth Count," The TeahgProfessor, vol. 10, no.10, December, 1996. 33. Eco, U., The Open Work, Harvard University Press, Cambridge, 1989, p. 6. 34. Catalano, G., "Some Ideas on the Teaching of Engineering Science: A Student-Centered Approach," Journal fEn,gineering Educaion, vol. 84, no.1, Jan.,1995, pp. 21-24. 35. Aeschylus, Promet3euBound, Penguin Classics, New York,1965.