Concurrent Parameters Date Format

I set a concurrent Parameters:

I use this sql and I want return CONVERSION_RATE

select CONVERSION_RATE  from GL_DAILY_RATES_V where from_currency='CNY' and to_currency='USD'  and USER_CONVERSION_TYPE=:$FLEX$.AP_SRS_APXINREV_DAILY_RATE_TYPE and fnd_date.date_to_displaydate(CONVERSION_DATE)    = :$FLEX$.FND_STANDARD_DATE

but not return data wen I run the concurrent

but query in data base ,I can get value

please help us ,tks