Submitted on: 11 February 2020.
Revised on: 16 March 2020.
Accepted on: 06 April 2020.
___________________COMMUNICATIONS OF THE ACM---ASSOC COMPUTING MACHINERY
http://reply.papertrans.cn/1/61/6036/6036-22.png
http://reply.papertrans.cn/1/61/6036/6036-23.png
Submitted on: 13 December 2001.
Revised on: 06 March 2002.
Accepted on: 30 April 2002.
___________________COMMUNICATIONS OF THE ACM---ASSOC COMPUTING MACHINERY
http://reply.papertrans.cn/1/61/6036/6036-25.png
Submitted on: 24 November 2017.
Revised on: 21 December 2017.
Accepted on: 17 January 2018.
___________________COMMUNICATIONS OF THE ACM---ASSOC COMPUTING MACHINERY
http://reply.papertrans.cn/1/61/6036/6036-27.png
Submitted on: 18 September 2019.
Revised on: 03 November 2019.
Accepted on: 24 November 2019.
___________________COMMUNICATIONS OF THE ACM---ASSOC COMPUTING MACHINERY
http://reply.papertrans.cn/1/61/6036/6036-29.png
Submitted on: 19 March 2008.
Revised on: 15 July 2008.
Accepted on: 12 September 2008.
___________________COMMUNICATIONS OF THE ACM---ASSOC COMPUTING MACHINERY