I have reviewed hundreds of resumes.
I rejected you (in this thread) before I got out out of THE TITLE of the thread (though I did give you the courtesy of reading the rest of the thread).
First thing I noticed- WHY focus on being noticed in "online applications"? It evidences to me a fear of dealing with someone face to face, and an unwillingness to take the risk and put in the effort. Online applications are important, but will return an EXTREMELY low percentage.
Which leads me to the second thing I noticed- If you are doing online applications, WHY only fifteen? I don't mean to be a harda$$, but that's an afternoon's work, not a job search. Your job search should include HUNDREDS of online applications, and dozens of walk-ins. I recommend 2-3 personal walk-ins PER DAY.
Third- no cover letter is death. I don't care what you've done. I want to see why you think you'd be a GREAT fit for MY company.
Fourth- stop focusing on your specific area of expertise. I'm glad to hear you have skills- so do thousands of other people I could hire. Re-write your resume to focus on your transferable skills (to other businesses and industries) and apply everywhere. Get a job SOMEWHERE doing SOMETHING, then move up the ladder or to another company. It is MUCH easier to get a job when you have one.
Now, let me give you a clue. I'm going to contradict everything I said. The best job search is not grenade style or shotgun style, it is sniper style. You should be interviewing the companies you want to work for, not begging anybody you can for a job. Do your homework. Research every detail you can about a company. Know who the owner is, how big his family is, and what his reputation is. Understand their primary business, and know what direction the company is headed. Know what charities they support, and the history of the company. Figure out the name of the receptionist before you walk in the door. Be prepared to sit in an interview and tell them why they need you, how excited you are about this new venture of theirs, or that new product line, and what you bring to the company.
I know this is outside of your comfort zone. That's OK, it's outside of everyone's. Sell yourself.
If you do it this way, you will KNOW who you want to work for before you get there (and WHY), you should land a job in 2 or less interviews, and you should be extremely satisfied when you get it.
Go get 'em.