I'm unsure how to write an optimization statement in clingo4 (ASP solver).
I want to minimize the total number of instances of certain literals in each answer set.
I'm simulating a fire-response agent in ASP. The agent can choose to perform certain simple actions at different times, such as:
0{call_fire_department(Area, Time, Time+1)}1:- [preconditions].
0{send_security_guard(Guard, Area, Time, Time+1)}1:- [preconditions].
0{activate_fire_suppression(Area, Time, Time+1)}1:- [preconditions].
The agent has goals, which require a mix of the above actions, at specific times. I want to minimize the number of instances of each of the above, while still achieving the agent goals.
How do I write an appropriate optimization statement? (I'm assuming I will need a 'minimize' statement).
Thanks.
How about
#minimize{
1, call, Area, Time : call_fire_department(Area, Time, Time+1) ;
1, send, Guard, Area, Time : send_security_guard(Guard, Area, Time, Time+1) ;
1, activate, Area, Time : activate_fire_suppression(Area, Time, Time+1)
}.
1 means count 1 towards the fact
Tag (call, send, activate), Guard, Area and Time make sure each fact is counted. E.g. without the tag activate_file_suppression(foo, 20, 21) and call_fire_department(foo, 20, 21) would be merged in the set.
Related
The "Assembler" should stop working for 2 hours after 10 assemblies are done.
How can I achieve that?
There are so many ways to do this depending on what it means to stop working and what the implications are for the incoming parts.. but here's one option
create a resourcePool called Machine, this will be used along with the technicians:
on the "on exit" action of the assembler do this (I use 9 instead of 10 because the out.count() doesn't count until the agent is completely out, so when it counts 9, it means that you have produced 10)
if(self.out.count()==9){
machine.set_capacity(0);
create_MyDynamicEvent(2, HOUR);
}
In your dynamice event (that you have to create) you will add the following code:
machine.set_capacity(1);
A second option is to have a variable countAssembler count the number of items produced... then
on exit you write countAssembler++;
on enter delay you write the following:
if(countAssembler==10){
self.suspend(agent);
create_MyDynamicEvent(2, HOUR,agent);
}
on the dynamic event you write:
assembler.resume(agent);
Don't forget to add the parameter needed in the dynamic event:
Create a variable called countAssembler of type int. Increment this as agents pass through the assembler. Also create a variable called assemblerStopTime. You also record the assembler stop time with assemblerStopTime=time()
Place a selectOutputOut block before the and let them in if countAssembler value is less than 10. Otherwise send to a Wait block.
Now, to maintain the FIFO rule, in the first selectOutputOut condition, you need to check also if there is any agent in the wait block and if the current time - assemblerStopTime is greater than 2. If there is, you free it and send to the assembler with wait.free(0) function. And send the current agent to wait. You also need to reset the countAssembler to zero.
So the problem is:
How can I change the amount in "Resource Sets" programmatically? I'am planning on changing this value back and forth from 1 and 2 given some conditions during the simulation run.
Amount I want to change is marked in yellow below.
Emile answer is right, but if you insist in using what you are using, you can click on the equal sign and make it a function:
and in the function (which i made take a random number between 1 and 2, but you can do what you want), you use the following (the function returns a type ResourcePool[][])
ResourcePool[][] rp = new ResourcePool[1][num];
for(int i=0;i<num;i++){
rp[0][i]=resourcePool;
}
return rp;
In your case, it seems you are using one resource alternative only.
Why don't you choose units of the same pool, then the number of units to be seized becomes dynamic.
I am very new at Anylogic. I have a simple model, using the Fluid dynamics library: two tanks and a valve between them. The valve have to open at a rate, say X, only when the amount in the first tank, say tank_1, were twice of the amount of the second tank, say tank_2
Could you please help me with that?
Regards
You probably have more conditions on what to use with the valve depending on different things. But it's a bad idea to make something occur when then tank_1 is exactly 2 times larger than tank_2... Instead, create a boolean variable that tells you if the current situation is that tank_1 is over or below 2*tank_2. Let's call it "belowTank2". I will assume tank_1 is below 2*tank_2 in the beginning of the simulation. so belowTank2 is true.
Then you create an event that runs cyclically every second or even more often if you want and you use the following code:
if(belowTank2){
if(tank_1.amount()>2*tank_2.amount()){
valve.set_openRate(0.1);
belowTank2=false;
}
}else{
if(tank_1.amount()<2*tank_2.amount()){
valve.set_openRate(0.3);
belowTank2=true;
}
}
So this means that whenever tank_1 surpases 2*tank_2, it will trigger the rate change on the valve. And it will trigger again a change when it's below 2*tank_2
I have a quick question about the details of running a model in JAGS and BUGS.
Say I run a model with n.burnin=5000, n.iter=5000 and thin=2. Does this mean that the program will:
Run 5,000 iterations, and discard results; and then
Run another 10,000 iterations, only keeping every second result?
If I save these simulations as a CODA object, are all 10,000 saved, or only the thinned 5,000? I'm just trying to understand which set of iterations are used to make the ACF plot?
With JAGS, n.burnin=5000, n.iter=5000 and thin=2, means you keep nothing. You run 5000, discard the first 5000 of these 5000 and then only keep a half of the remaining values of the chain (keep 1 value and discard the next one ..).
Use for example n.burnin=2000, n.iter=7000, thin=50, n.chains=5 : so you have (7000-2000)/50 * 5 = 500 values.
Could you be more specific which software you're talking about? It looks like you're referring to the arguments of the function bugs() in the R2WinBUGS package (except that the argument is called n.thin not thin). Looking at help(bugs) it just says n.burnin is the "number of iterations to discard at the beginning". Which doesn't specifically answer your question, but looking at the source for bugs.script() in that package suggests to me that it would run 5000 iterations burn in, as you suspected. You could send a suggestion to the maintainers of that package to clarify their documentation.
In your example, bugs() would then run 0 further iterations after the burn-in. Here the documentation is clearer - n.iter is the total number of iterations including the burn-in.
For your second question, the CODA output from WinBUGS (and any software which calls WinBUGS or OpenBUGS) will only include the thinned sample.
During the reading of PLC documentation (Omron CP1L PLC and CX-Programmer), there are some missing explanation. For example, it defines "Flag" as "a bit that serves as an interface between in*struction", does that mean flag is some sort of conditional Power Flow?
It gets more confusing with the terms "Differential Up/Down", "Carry Flag"? What are flags and what do they do in the ladder logic? Are they a simple or instruction to use or just a concept that I don't really need to program in ladder?
[EDITED]
Where to add / modify / delete the flag in an instruction? I open up the edit but flag isn't there.
Ok, this is a better question.
PLCs are like any program - data is stored as different types. Think of flags as interchangeable with the term "bit", "boolean", etc. They are very important.
If you have CX-Programmer, a much better place to get information is the Instruction Reference (Help --> Instruction Reference --> yourPLC). These show time diagrams of most of the instructions and how each of the parameters and flags operate.
For example, a basic timer (TIM) works by assigning it a value. If you use a BCD type 100ms timer and assign its SV (setpoint value) a BCD value of 300 then you have created a timer with a 30 second limit (300 x 100ms). When the timer turns on it will begin counting and the PV (process value) will start from 300 and count down. When the value reaches zero the timer's flag turns ON to indicate that it has expired. If the timer's number is, say T100 then you can use T100 as a contact in another rung of logic - it will be true when the timer's execution conditions are TRUE and the timer has expired.
Differentials (UP/DOWN) are special flags which are true for only one PLC scan (ie: they are true for one execution cycle only) when their input conditions change from FALSE to TRUE (ie:OFF to ON) for UP differentials, and TRUE to FALSE (ie:ON to OFF) for DOWN differentials. You would use differentials in cases where you wanted to perform an action the moment a given condition changes.
Flags can be used for almost anything. You can use them as general booleans in your own programs, they can be parts of certain operations (ie: the CY (carry) flag is used on arithmetic operations which result in a carry - other flags are used to indicate overflows or div/0 errors, etc).
Edit again : (to answer extended question).
A basic timer's completion flag is a contact with its number. Say I have a 100ms timer, T100, which turns on when contact 10.00 is on:
10.00 ___
|-----| |---------------------------------------|TIM|
|100|
| |
|#20|
|___|
Now, once 10.00 has been ON for two seconds, the timer will elapse and the flag for timer 100, T100, will turn ON. If I had another rung where
| T100 W15.00
|-----| |-----------------------------------( )
Then work bit W15.00 would be turned on when the timer elapsed and would remain on so long as the timer's input condition remained satisfied (ie: so long as 10.00 remains ON). Flags work in different ways for different things, however. Each operation can use them in different ways.
The example from the Omron Instruction Reference (Help -> Instruction Reference -> [select PLC]) looks like this :
Well very good explanation with example and the flags value can be found in memory area it is pure binary either 0 or 1, as i was read the documentation work-bit memory location changes as per timer type e.g TIM/TIMX or TIMH or TIMHX, both are BCD timers but unit for the timer changes.