From a viewpoint of someone who is not in your class and without the text in front of me, I found this video to be very helpful. This was very helpful in explaining the rule and the sequencing(something I found confusion in the way my text explained it). Thank you very much!! The video is clear and concise.
being an industrial engineer and excel fanatic, i find this video informative but you do have some gaps on the explanation but still better than other vids on YT
There really isn't an easy way to schedule a process that has more than two operations. This is where you get into more complex computer modeling. One way to work around that is to find those two operations in the process that seem to have the most variability (differences between the two operations) and use the Johnson's rule on those two operations. Remember that the two operations have to be done in order. If there wasn't a sequence or order to the operations, which operation must be done first before the other second operation can be done, there would be no need for Johnson's rule. If we have identified the two sequential operations in the process that have the most variability and used Johnson's rule, then we will have at least efficiently scheduled those two operations. The only problem may be sub optimization if the process has a lot of operational steps. This is when a computer simulation is the best because it can examine all of the possible combinations or schedule of jobs and calculate completion times and therefore give you the best or optimal scheduling based on the sequencing of jobs that provide the quickest completion time and the least amount of idle time.
I created these videos many years ago when I was teaching a course. I am sure there have been many new editions of the textbook since then and the authors have probably rearranged or renumbered the practice problems at the end of the chapter. The videos were created to help my students that were taking the course at the time. I haven't taught this course for some time and thought about deleting the videos but it appears they have been helpful to others. One of these days, I need to redo the videos and just get rid of the reference to specific problem numbers.
The questions were drawn from a very old edition of Management Operations by Render and Heizer. It is probably out of print. These videos were produced many years ago when I was a professor.
Hello, i had successfully made johson's rule in C++ until sequence,, now the problem is how to calculate Cmax in Program,, can anyone help me with it ?
+Joseret Garcia If you look at the diagram I created at the end to show you the effect of Johnson's rule and doing it in the order suggested by Johnson's rule, you will notice that I eliminated gaps that may have occurred if they weren't scheduled properly using Johnson's rule. There are a couple of hours of idle time for the 2nd workstation while they wait for job E to be sanded before the painting (2nd workstation). Sometimes, they count the idle time of 1st workstation (sanding) at the end which would be 4 hours. However, I usually don't count this because there is no reason for them to stick around since all of the jobs for that workstation have been completed. In a similar manner, I guess you could schedule those involved in 2nd workstation to come in 2 hours later and therefore, you would have no idle time. Johnson's rule cannot always eliminate all idle time from in between jobs like it did in this case but I will minimize idle time in 2nd workstations.
Adam Kelly Given the parameters (sequencing jobs on two machines that must be done in order), Johnson's Rule will provide you with the optimal solution. There may be other ways to achieve this but Johnson's Rule is probably the easiest way to determine the optimal solution.
The only way to really figure this out, is to do the "bar chart" as shown in Excel. It will take 35 hours to complete all of the jobs (each cell represents one hour). This is a little idle time at the beginning for workstation #2 (painting) but Johnson's Rule to eliminate the idle time that would have happened had the jobs just been done in order.
+anup Kulkarni I am not sure what you mean by ideal time. By following Johnson's Rule, one will achieve the shortest time possible because the procedure schedules the jobs in such a manner as to minimize idle time. Idle time is the time where workstation #2 is waiting for the job to be finished on workstation #1. Johnson's Rule will minimize those gaps but one still may have a few because workstation #1 (first process or machine) has to be completed first for every job and then the job can go to workstation #2 (second process or machine). Johnson's Rule shows you how to load or sequence the jobs correctly on workstation #1, so that the gaps or idle time is minimized for workstation #2. The easiest way to determine idle time and see Johnson's Rule in action is to graph (visual representation of the time on each workstation) the data and see where there are still gaps. Johnson's Rule cannot necessarily eliminate all gaps but it will be better than just doing the jobs in any random order.
I'm sorry, but this was terrible. You hardly explained anything and spent 6 Minutes struggling with the graphics, which you should have prepared and just paste them in or whatever. And a before/after optimizing would have been great to actually see the difference. Though I admit you did apply the Johnson Rule...
The video was created in conjunction with a course that I am teaching in operations management and corresponds to a homework problem from the textbook. Students usually have the homework problem in front of them as they are watching the video. As part of the solution, students have to create the diagram in Excel for their assigned homework problem. If I was creating this video just for the general public, I would have done it differently and just pasted the graphic in and shown the differences between using Johnson's Rule and just putting them in order listed. However, most of the students in the class ask me how to create the graphic in Excel and that is why I took the extra time to show them how to do the graphic. I also create all of these videos (one for every homework problem assigned in the class) last semester and tried to do them in one take. I do need go back and fix some of them. Thank you for your comments. I will see if I can improve this one.
From a viewpoint of someone who is not in your class and without the text in front of me, I found this video to be very helpful. This was very helpful in explaining the rule and the sequencing(something I found confusion in the way my text explained it). Thank you very much!! The video is clear and concise.
This was really good! I was programmatically implementing Johnson's rule and this opened my mind to the chart part.. Thank you very much!
I am glad you found it useful
I appreciate this video, it was really helpful.
Thank you!
I am glad that you found it helpful.
Super clear explanation. Thank you!
Amazing vid.
great job man I think you did a great job at explaining this. I too am taking om 301
Very and clear useful explanation. Thank you!
I am glad you found it useful
being an industrial engineer and excel fanatic, i find this video informative but you do have some gaps on the explanation but still better than other vids on YT
Thanks. These videos were primarily designed to help my students. My students had the benefit of attending class to fill in some of the gaps.
nice and clear. why my profesor didnt explain in this way. 1,5 h blablabla and here 11:04 thanks a lot 😀
I enjoyed reading your comment. Thank you that made my day. My students probably see me the way you see your professor.
Thanks a lot
thanks for the simplified video
Thanks for the simple video.
Thank you so much 💕
You are so welcome
Thank you Sir!
I am glad you found the video helpful
Thank you, thank you!
I am glad that the video was helpful
Can you explain how to use Johnson's rule if there where more than two operations to be done?
There really isn't an easy way to schedule a process that has more than two operations. This is where you get into more complex computer modeling. One way to work around that is to find those two operations in the process that seem to have the most variability (differences between the two operations) and use the Johnson's rule on those two operations. Remember that the two operations have to be done in order. If there wasn't a sequence or order to the operations, which operation must be done first before the other second operation can be done, there would be no need for Johnson's rule. If we have identified the two sequential operations in the process that have the most variability and used Johnson's rule, then we will have at least efficiently scheduled those two operations. The only problem may be sub optimization if the process has a lot of operational steps. This is when a computer simulation is the best because it can examine all of the possible combinations or schedule of jobs and calculate completion times and therefore give you the best or optimal scheduling based on the sequencing of jobs that provide the quickest completion time and the least amount of idle time.
Correction you actually used the data from problem 15.23 not 15.18
I created these videos many years ago when I was teaching a course. I am sure there have been many new editions of the textbook since then and the authors have probably rearranged or renumbered the practice problems at the end of the chapter. The videos were created to help my students that were taking the course at the time. I haven't taught this course for some time and thought about deleting the videos but it appears they have been helpful to others. One of these days, I need to redo the videos and just get rid of the reference to specific problem numbers.
@@carycountryman That makes sense, You helped me understand how I was going to graph this problem in excel so thank you.
which textbook do you get the questions from?
The questions were drawn from a very old edition of Management Operations by Render and Heizer. It is probably out of print. These videos were produced many years ago when I was a professor.
Hi cary . Need ur help in one my example can u help me
Hello, i had successfully made johson's rule in C++ until sequence,, now the problem is how to calculate Cmax in Program,, can anyone help me with it ?
How do you come up with the idle time of 2 hours?
+Joseret Garcia If you look at the diagram I created at the end to show you the effect of Johnson's rule and doing it in the order suggested by Johnson's rule, you will notice that I eliminated gaps that may have occurred if they weren't scheduled properly using Johnson's rule. There are a couple of hours of idle time for the 2nd workstation while they wait for job E to be sanded before the painting (2nd workstation). Sometimes, they count the idle time of 1st workstation (sanding) at the end which would be 4 hours. However, I usually don't count this because there is no reason for them to stick around since all of the jobs for that workstation have been completed. In a similar manner, I guess you could schedule those involved in 2nd workstation to come in 2 hours later and therefore, you would have no idle time. Johnson's rule cannot always eliminate all idle time from in between jobs like it did in this case but I will minimize idle time in 2nd workstations.
is johnson's rule the only method that is optimal for 2 machine?
Adam Kelly Given the parameters (sequencing jobs on two machines that must be done in order), Johnson's Rule will provide you with the optimal solution. There may be other ways to achieve this but Johnson's Rule is probably the easiest way to determine the optimal solution.
how long does it take to complete the jobs?
The only way to really figure this out, is to do the "bar chart" as shown in Excel. It will take 35 hours to complete all of the jobs (each cell represents one hour). This is a little idle time at the beginning for workstation #2 (painting) but Johnson's Rule to eliminate the idle time that would have happened had the jobs just been done in order.
sir how to calculate ideal time
+anup Kulkarni I am not sure what you mean by ideal time. By following Johnson's Rule, one will achieve the shortest time possible because the procedure schedules the jobs in such a manner as to minimize idle time. Idle time is the time where workstation #2 is waiting for the job to be finished on workstation #1. Johnson's Rule will minimize those gaps but one still may have a few because workstation #1 (first process or machine) has to be completed first for every job and then the job can go to workstation #2 (second process or machine). Johnson's Rule shows you how to load or sequence the jobs correctly on workstation #1, so that the gaps or idle time is minimized for workstation #2. The easiest way to determine idle time and see Johnson's Rule in action is to graph (visual representation of the time on each workstation) the data and see where there are still gaps. Johnson's Rule cannot necessarily eliminate all gaps but it will be better than just doing the jobs in any random order.
Please on translate for Indonesia 🙏
I sorry that I don't speak any foreign languages. I don't know how I would translate this for Indonesia.
I'm sorry, but this was terrible. You hardly explained anything and spent 6 Minutes struggling with the graphics, which you should have prepared and just paste them in or whatever. And a before/after optimizing would have been great to actually see the difference. Though I admit you did apply the Johnson Rule...
The video was created in conjunction with a course that I am teaching in operations management and corresponds to a homework problem from the textbook. Students usually have the homework problem in front of them as they are watching the video. As part of the solution, students have to create the diagram in Excel for their assigned homework problem. If I was creating this video just for the general public, I would have done it differently and just pasted the graphic in and shown the differences between using Johnson's Rule and just putting them in order listed. However, most of the students in the class ask me how to create the graphic in Excel and that is why I took the extra time to show them how to do the graphic. I also create all of these videos (one for every homework problem assigned in the class) last semester and tried to do them in one take. I do need go back and fix some of them. Thank you for your comments. I will see if I can improve this one.