According to the Coast Guard Academy Web site, since 1976, 744 women have graduated from the academy.
Keene was salutatorian of her class at North Hagerstown High School.
At the Coast Guard academy, she graduated fourth in her class and went on to hold a number of positions in the service. She continued her education, earning a master's degree in business administration at the University of Honolulu, where she won the Lum Yip Kee award as top graduate. She also was a National Security Fellow at Harvard University.
Keene, who was promoted to captain in 2003, said that when she entered the service, women did not hold high-ranking positions. Today, Vice Admiral Vivien S. Crea is vice commandant, making her the Coast Guard's second in command.
In 2006, Keene returned to the academy in New London, Conn., as the 31st commandant of cadets -- the first woman to be assigned to that position.
The post is comparable to that of dean of students at a public university. As commandant of cadets, Keene helped train cadets in all aspects of military life, turning them from civilians into future mariners.
Keene joked that when her two daughters left for college and she accepted the commandant position, she traded her two children for 1,000.
"Working with students provided me with an energetic and youthful outlook to life. I helped shape the future of our nation by helping students enter into serving our country, making sacrifices for their fellow Americans. That's a great feeling," Keene said.
One of Keene's favorite positions involved acting as group commander of the Coast Guard Group, Woods Hole, Mass., in 2003. In that post, she oversaw the operation of eight multimission small-boat stations, one seasonal station, four patrol boats, two aids to navigation teams and a long range of aids to the navigation station.
Throughout her tenure, Keene was responsible for search-and-rescue missions, monitoring boater safety, law enforcement mission assignments and gender policy revision.
Keene's leadership earned her an assortment of medals and awards, including, but not limited to, the Meritorious Service Medal with the Operational Distinguishing Device, the Secretary of Transportation's Silver Medal and the Coast Guard Achievement Medal.
During her career, Keene and her husband, who also is a captain in the Coast Guard, "were never judged or compared based on our gender, but whether or not we could competently complete the task at hand," Keene said. "For me, pregnancy and marriage didn't factor in to how well I did my job. It's all about dependability."
Keene's mother, Doris Lake of Hagerstown, said that although she and her husband were nervous about their daughter entering the Coast Guard, she proved to be capable of facing any task.
Over the past 31 years, Keene said, the academy and the Coast Guard in general, have changed the most in the use of advanced technology and in the area of gender equality.
"There's so many women at the academy now," she said. "It's a lot more normal to see women in every aspect of military life -- in academics, athletics and all forms of militaristic training."
She said that although women faced unique challenges, both sexes are equally trained to serve their nation to the best of their abilities.
As far as the future of the Coast Guard is concerned, Keene said, "Our role will continue to grow and our law-enforcement tradition of enforcing drug laws and interceding illegal aliens, while keeping the waters safe, will always be needed, but we will have to continue to take on ever-increasing responsibility in homeland security as threats continue to increase."
Keene took time off to travel with her husband, who followed her into retirement weeks later.
Keene said she was uncertain about her future career but said she plans to contribute to the world around her.