I'll try and keep it simple : I've started using Arena Simulation for studies purposes, and up until now, I've been unable to find any conclusive documentation or tutorial as to how to create a Job Shop, if you could direct me to specific and practical documentation, or otherwise a helpful example which could get me started , that would be most helpful.
My problem : A given number of jobs must be processed through a given number of ressources (machines), each job has a different route to take, and each one has a different work-time depending on the resource it is using.
Ex : For job_1 to be finished, it must first use ressource_1 with 5 seconds execution-time, then ressource_3 with 3 seconds execution-time and finally ressource_9 with 1 second execution-time. Of course, a different job has a totally different route and different execution-times.
Here's an MS thesis I found...
http://www.scribd.com/doc/54342479/Simulation-of-Job-Shop-using-Arena-Mini-Project-Report
ADDENDUM:
The basic idea is to use ASSIGN to label the jobs with attribute variables reflecting their routing requirements. Those attributes can be read and used by decision blocks to route the job to the appropriate next workstation or to the exit. Perhaps these notes will be more useful to you than the MS thesis cited above. That's about all I can give you since I haven't used Arena for several years now -- I no longer have access to it and can't put together any specific examples.
Related
I am trying to simulate a manufacturing assembly process, where material items are processed following an unique line. In the quality control stations, when a failure is detected, the object is sent to the repair area (by a truckpallet) and, when it is repaired, the same resource takes it and puts it at the start of the line. Until this point, I already programmed it.
The problem is the following: when it is a repaired object, is has to follow the same conveyor but with no stops in the stations. The object must enter a station and leave it, with no delays (as the works related with the stations have already been made).
I thought the best would be to consider the difference (repaired vs. not repaired) in the Agent, but then I can't work with it in the Main agent... I have also tried alternative solutions, for example defining variables in each station 1 and consider that in the stations delays and in the following station:
triangular( 109.1*delay_bec, delaytime_bec*delay_bec, 307.6*delay_bec)
Actions - in finished process:
if(delay_bec==0){
delay_headers=0;
delay_bec=1;}
But nothing worked... Any help?
I thought the best would be to consider the difference (repaired vs. not repaired) in the Agent, but then I can't work with it in the Main agent...
This is actually the correct approach. You need to create a custom agent type, give in a boolean variable isRepaired (or similar) and then in the delay you can dynamically adjust the duration using that characteristic:
agent.isRepaired ? 0. : 100
This will delay normal agents by 100 time units and repaired agents not at all.
Obviously, you must make sure that the agents flowing through the flow blocks are of your custom agent type (see the help how to do that)
I am using Anylogic for a simulation-modeling class, and I am not anylogic or coding smart. My last and only coding class was MatLab based about 16 yrs ago. I have a few questions about how to implement modeling concepts in a discrete model with anylogic.
How can I add/inject agents directly into a queue downstream from a source? I have tried adding an additional source to use the “Calls of inject() function,” but I am not sure how to implement it after selecting it ( example: what do I do after selecting the Calls of inject() function). I have the new source feeding directly into the queue where I want the inject.
How can I set the release of an agent to a defined schedule instead of a rate? Currently, I have my working model set to interarrival time. But I would like to set the agent release to a defined schedule. (example: agent-1 released at 120 seconds, agent-2 released at 150 seconds, agent-3 released at 270 seconds)
Any help would be greatly appreciated, especially if it can be written in a “explain to me like I am 5yrs old” format.
Question 1:
If you have a source connected directly to a queue, then when you call source.inject() an agent will be created at the source block and go to the queue. If you have 1 source with multiple possible destinations, then you will have to use select output blocks and some criteria to go from the source to the desired queue.
Since you mentioned not being a strong programmer, this probably wouldn't be for you, but I often find myself creating agents via add_population and then just adding them to an ArrayList until I am ready to pull them into the DES flow. Really, there are near infinite ways to control agent flow within AnyLogic.
Question 2:
Option a: Arrivals by "Arrival Table in Database" You can link an AnyLogic database table to Excel, and then the source block will just have an agent arrive based on that table.
Option b: Arrival Schedule - you could set this up manually within the development environment or load your schedule from a database. I prefer option a over option b given your brief description.
Option c: Read in data to variable and then write code to release based on next arrival time. 1,000s of ways to do this, but one example could be a list of doubles (your arrival times), set an event to delay until next arrival, call inject function, remove that arrival from the list. I think option a would be best for you, but given that AnyLogic allows you to add java code, there are no limits to how sophisticated you could make your arrival logic.
For 2) You could also use an event or a dynamic event. The action could be source.inject(1); and you can schedule them to your preferences with variables. Just be vigilant that you re-start the events if necessary.
There is a demo-model from AnyLogic for dynamic events.
I am modeling ticket system with various SLA. The model must contain several service blocks with different reaction time ( from 2 to 32 hours). In the service block only working hours should be taken into account. So in the service block timeout should stop when non-workong hours and on the weekend. Could you please kindly tell me how i can realize it?
Thank you very much in advance!
I can think of two answers, one simplified but works in many cases, the other more advanced and probably more accurate:
Simplified approach: I would set the model in hours and keep everything running as is without any stop. So, at the end of the simulation, if the total time is 100 hours and you know that you have 8 hours/day with 5 days/week, then you'd know the total duration is 2.5 weeks. Of course, this might have limitations or might become more complex later on if you want day-specific actions (e.g. you want to differentiate between Monday, Tuesday, etc.)
Advanced more accurate approach: Create resources whose capacities are defined by schedule and assigned them to your services. Create a schedule and specify the working hours in that schedule. Check the below link to learn more about schedules. I call this the more advanced approach because you need to make sure the schedule is defined correctly and make sure all elements in the model are properly controlled (e.g. non-service blocks such as source, delays, etc.).
https://help.anylogic.com/topic/com.anylogic.help/html/data/schedule.html?resultof=%22%73%63%68%65%64%75%6c%65%73%22%20%22%73%63%68%65%64%75%6c%22%20
I personally would use the first approach if the model is rather simple and modeling working hours is enough for analysis. Otherwise, I'd go for option 2.
Finally, another option I'd like to highlight is the "suspend/resume" functions. I am only adding this because you asked "how to stop timeout". So these functions specifically stop and resume timeout. But you'll need to define the times at which they are executed (through an event for example).
Basically I've got a Service which can work with two alternatives of ResourceSets. Let's say, the Service would optimally work with one Doctor and one Nurse, but it is also possible to work with only one Doctor if a Nurse isn't available.
Now, assuming the Doctor works slower without a Nurse, the Service's delay time must depend upon the resourceSet being employed at the moment (Doctor+Nurse or Doctor). Any idea how can I program this?
You should also have in mind that my model has various Services in parallel working in the same way, it's not just only one Service line.
Thanks!
You're using Services but, to me, using the combination of Seize, Delay and Release gives you more flexibility.
What I've done is set the resource choice according to the image bellow:
It is important to have the nurses prior to the doctors in the first set (for some reason anylogic would opt for using only the doctor if otherwise - even with a nurse available).
Than, I would write this code:
Which means that if the agent was only able to seize one resource it will take longer (15 is just a random value).
In the delay block, I would set the processing time to agent.processTime
The topology I'm using is this:
Obviously this is a workaround and will not work for every case. You can always change the conditions you verify. I couldn't find a way to check which resource set was picked by the seize operation. If you're in a hurry this will do the trick.
Hope that helps,
Luís
I have a real-time workflow for creating unique numbers. This workflow get a numeric field from my custom entity, increase it by 1, and update it for next use.
I want to run this workflow on multiple records.
Running on-demand mode, it works fine,and I have true and unique numbers, but for "Record is Created" mode, it dose not work fine and get repeated numbers.
What I have to do?
This approach wont work, when the workflow runs on demand its running multi-threaded, e.g. two users create two records, two instances of the workflow start. As there is no locking mechanism you end up with duplicated numbers.
I'm guessing this isn't happening when running on demand because you are running as a single user.
You will need to implement a custom auto number approach, such as Auto Number for DynamicsCRM.
Disclaimer: I work for Gap Consulting who produce the tool linked above.