[SalesForce] SQL Query in Marketing Cloud Today = date

You'll need to consider the time portion of the dates. Here's a sargable way to do it:

SELECT * 
FROM [UG Journey Master]
WHERE [dateofApplication] >= DateAdd(day,-15,cast(GetDate() as date))
and [dateofApplication] < DateAdd(day,-14,cast(GetDate() as date))

Casting getDate() as a date, will reset the time part of the date to zero (midnight).

Update (20170804)

Here's a more efficient way to do it:

SELECT * 
FROM [UG Journey Master]
WHERE [dateofApplication] >= convert(date,getDate()-15)
and [dateofApplication] < convert(date,getDate()-14)

If you just want rows from yesterday, you can do something like this:

select
request_date,
convert(date, request_date) as request_date1
from temp
where convert(date, request_date) >= convert(date, getdate()-1)
and convert(date, request_date) < convert(date, getdate())

If your request_date is actually a date datatype in SFMC, then you can simplify it like this:

select
request_date
from temp
where request_date >= convert(date, getdate()-1)
and request_date < convert(date, getdate())