Five Kellogg M.B.A.'s recently won the MOOT Corp. International Entrepreneurial Challenge, an annual competition, held at University of Texas at Austin, among a dozen business schools worldwide. In the challenge students compete to come up with the best and most feasible growth-oriented business concept. The winning entry: Independence Marine, which will manufacture and direct-market products that help fishermen keep whales, porpoises, dolphins, and seals out of their nets. The first product -- still being tested for approval by U.S. and Canadian fisheries departments and expected to be rolled out next spring -- is a small noisemaking device called Whale Away. It attaches to a net and makes enough sound to alert whales to stay clear. John Hattery, 30, got the idea for the business last year when he read about a Newfoundland inventor named Jon Lien. Lien had developed a medieval-looking metal soccer-ball-shaped noisemaking device and was having trouble figuring out how to manufacture and market it cost-effectively. The five students -- all engineers specializing in manufacturing -- redesigned it and reduced the price from $250 to less than $40. Hattery projects first-year revenues for Independence Marine of $100,000 (mostly from the sale of test models), and $1.3 million in 1994 revenues.