As travelers' fears diminish with the conclusion of the Persian Gulf war amid signs of an easing of the recession, several major cruise lines have moved to raise their rates.

Many cruise lines had offered discounts or deferred price increases during the war.Carnival Cruise Line has announced an increase of about 5 percent on its three-, four-, and seven-day cruises.

In addition the rate for cruises aboard Carnival's Fantasy megaship will be raised nearly 10 percent.

Bob Dickinson, Carnival's vice president of sales and marketing, said the increase was approved because the Fantasy cruise was initially "underpriced."

The new rates will go into effect on June 15. The price for a seven-day cruise will run from $999 to $2,439.

The four-day Carnivale and Mardi Gras Cruises will cost from $529 to $1,159; the three-day cruises will range from $399 to $1,019.

Four-day rates for the Fantasy will be $579 to $1,319; three-day rates will be $459 to $1,149.

Other major cruise line rates will be adjusted as follows:

Norwegian Cruise Line, which has already increased rates by 5 percent this year, has not determined whether its 1991-92 prices will rise.

Royal Caribbean Cruise Line, which raised its rates 3 percent this year, plans a further 3 percent increase in June.

Princess Cruises plans to maintain all current rates, except for its Caribbean cruises, which will go up $50 a person next Jan. 4.

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The Federal Aviation Administration is allowing domestic airlines to reinstitute curbside check-ins with appropriate security measures.

A spokesman for the Airport Operators Council International said the move would reduce congestion and delays at airports since an estimated 40 percent of passengers check their baggage at the curb.

Security is being refocused, not lessened, the spokesman said, since a specific credible threat as a result of the gulf war was not received at any airport.

Airports will now be able to concentrate on maintaining security in the terminal areas.

Skycaps or ticket counter representatives with security training will closely monitor all curbside check-ins, and, as before, only ticketed passengers will be allowed beyond screening points.

The FAA has also authorized airports to reopen some parking spaces near the terminal buildings closed during the gulf war.

O'Hare Airport in Chicago plans to open about 1,500 spaces, and Kennedy International Airport in New York will reopen rooftop parking lots.