First i would thank CKPT for this amazing article that post in his blog .
Instead of reviewing whole alert log file for any Particular information, We can search using that key word from X$DBGALERTEXT Table.
Grep The word “Starting Up” of Alert log file from Instance.
col ORIGINATING_TIMESTAMP for a40
col MESSAGE_TEXT for a80
set linesize 500
SELECT
originating_timestamp,
message_text
FROM
sys.x$dbgalertext
WHERE
message_text LIKE '%Starting up%';
Grep The word “Instance shutdown complete” of Alert log file from Instance.
SELECT
originating_timestamp,
message_text
FROM
sys.x$dbgalertext
WHERE
message_text LIKE '%Instance shutdown complete%';
again thank you CKPT for this article since its useful for all DBA’s , you can check CKPT Blog From the above link
Thank you
Osama mustafa
Technology Geek 
Very helpfull thank you
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Mustafa,Today I saw your blog, thanks for Your comments and for referring my blog.– Nassyam Basha
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@Mesli : your welcome , and can back to me any time
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Nassyam Basha Your welcome , no need to thanks , Hope to see you in Open World .
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Osama,I do not have plans to attend OOW, it's long way for me. So you attending? All the best.
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its the same here Nassyam , But it will be my first attending.
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Great info!file tracking systemfile sharing
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Thank you
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