# Questions tagged [scheduling]

For questions about methods that assign resources to work requests (e.g. processor time to tasks) usually minimizing some cost measure (e.g. makespan).

139 questions
Filter by
Sorted by
Tagged with
1 vote
61 views

### How to formulate fleet Assignment Problem?

I do want to formulate a fleet assignment problem. The following table is available It shows the departure/arrival location and time I am trying to find the min number of required planes to assign to ...
33 views

### Assignment/scheduling how to formulate considering job time and job cost

I have the following problem that I do not know how to formulate. There are a fixed number of workers $w_i \in W$ for $i \in [1…N]$. Also, there are a fixed number of jobs that must be assigned to ...
1 vote
43 views

### Minimize cost given working days/hours/required hours per job/start & end dates

I am trying to solve an optimization problem on Excel or Python. My constraints are the available number of employees (=20), the number of working days/month (=20), the number of working hours/day (=8)...
71 views

### Accelerating an integer programming model

I am working on a scheduling problem, where I am solving it through column generation. The pricing problem of this algorithm is an integer programming model as follows: F_1 \Big\{V^...
369 views

### What is the difference bewteen CP and MILP approaches in Job Shop Scheduling?

My understanding is Constraint programming (CP) is a sub-set of MILP but in MILP we not only try to find a feasible solution (like CP) but also we should optimize an objective function. I do have a ...
210 views

### Identifying problem: Assignment + Job Shop Scheduling

I am new to OR. Hence, I want your advice on the problem I am trying to solve: Given: $O_1 \rightarrow O_2 \rightarrow O_3 \rightarrow ... \rightarrow O_n$: the sequence of operations to produce $1$ ...
69 views

### Scheduling optimization, Adding 4 day same shift and 3 day off weekly constraint

Am writing a small scheduling program in C# for a group of 7 staff who will be working in three shifts daily for 4 weeks. Am using the google OR-Tools Template, but i have modified it abit This is the ...
105 views

### Np-hard sequencing or packing problems with total ordering between elements

I would like to know if anyone is aware of any Np-hard problems in scheduling or packing where there is total ordering between tasks or items to be packed together. The objective can be anything. For ...
239 views

### Visualizing results to the RCPSP

Bot for getting better insight and reporting purposes, I am looking for a way to visualize results to the Resource-Constrained Project Scheduling Problem (RCPSP). I am aware that such results are most ...
140 views

### Mathematically formulating formal problem of a cloud service scheduler

So, I have been tasked to create a formal mathematical description of problem statement on a cloud service scheduler for my team's university project, which is, honestly, a little weird of a thing to ...
144 views

### crew scheduling problem with shift priority hard constraints

I am working on a crew scheduling problem formulated as a MIP binary optimization where each employee is represented by a binary variable $X_{ids}$ s.t. $i \in I$ is $i$th employee, $d \in D$ is the ...
178 views

### How to model this user packing problem?

I have a system with $N$ resources. There are $K$ users in the system demanding these resources. The demand of resources for a given user $k$, $d_k$ follows $d_k\in\{1,3,6\}$ The constraints for this ...
131 views

### Project task scheduling based on available budget per period

I have a challenge that is a bit backwards from the usual labour resource leveling problem. In my case I have a fixed budget pool over a period to deliver some of the work packages (not enough per ...
121 views

### Job scheduling for a 2 stage job with 2 machines available for each stage

I am trying to solve a problem where I am provided a list of jobs that need to be scheduled to minimize the processing time. Every job has to be performed in 2 stages where the second stage can be ...
458 views

### Scheduling problem data generation

I compare the strengths and weaknesses of paradigms and approaches within those paradigms for solving machine scheduling problems. The amount of real-world data I have is limited and (random) ...
148 views

### Circuit constraints in ortools

I am looking to assign tasks to people. Each successive task should be started after the first one is finished and should be started at the same location as the preceding task. While the time ...
58 views

### MIP gives out zero as best solution when trying to optimize MIP model for flexible job-hop

I have implemented an existing MIP Model into python with the python-mip solver and somehow I only get '0' as a solution to my minimization problem. What could be the problem? I am fairly new to LP ...
59 views

### Determining constraint relevance in crew scheduling problem

I am working on a crew scheduling problem formulated as a MIP binary optimization where each employee is represented by a binary variable $X_{ids}$ s.t. $i \in I$ is $i$th employee, $d \in D$ is the ...
108 views

### opposite of no_overlap constraint in docplex for CP

I am using python for CP solving. I would like to know if there is constraint that does the opposite of no_overlap. This will be like overlap(interval, arr, n) interval - single interval variable arr -...
119 views

### Best known results on the flexible jobshop benchmarks

Is there a website that compiles the best known results on the flexible jobshop problem ? I know there was a blog post/article by Quintiq, a (deleted) blog post on CP Optimizer, some more recent ...
76 views

### Where I can study some job shop scheduling by course (video )?

I am seeking the help to know where I can study the job shop scheduling Heuristics or using solver by some course/video as I see some of books and papers hard to understand . It is hoped that the ...
376 views

### Python "Coffee Shop Scheduling Problem" - Scheduling Lunches/Breaks

I'm working on an employee scheduling program in python. Having never done this before, I've been researching different libraries that can be used to accomplish the task. Unfortunately, none of the ...
42 views

### RCPS with time buckets for resource capacity constraints

Goal: My goal is to come up with a Resource-Constrained Project Scheduling (RCPS) model where the resource capacity constraints are aggregated and verified on time buckets, which can be of varying ...
116 views

### "Complex" scheduling problem model structure

So, I'm modelling a job assigning problem in OR-Tools CP-SAT. I want to maximize rescheduled jobs based on some constraints. Right now jobs in my model look like this: ...
1 vote
102 views

### Need help with writing short proof related to Critical-Path-Method in scheduling with variable activity duration

I am currently working in the area of operations research / scheduling and am attempting to write a short proof. We are working with a directed acyclic graph of activities (Activity-on-Node-...
862 views

### What is the difference between job shop scheduling and resource constrained project scheduling?

I read here https://slideplayer.com/slide/3353960/ that RCPS is a generalized version of job shop scheduling. I'm new to this area and I'm trying to classify a specific variation of these types of ...
1k views

I changed jobs recently to a manufacturing firm. Job shop scheduling is made 100% manually and intuitively in Excel. Very time consuming and they have no idea if the schedule made is something close ...
111 views

### Dichotomic search for biobjective linear program, max flow problem for hospital patients

I recently asked this question about formulating a max flow diagram for hospital patients. I am now considering a secondary objective which is to maximize the effetiveness of the scheduled treatment. ...
562 views

### How exactly does OptionalIntervalVar work in OR-Tools?

I created OptionalIntervals for a number of tasks: ...
1 vote