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‎RunCode.md‎

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### 2. Clone [SDAPOMDPs.jl](https://github.com/CU-ADCL/SDAPOMDPs.jl)
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```bash
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git clone https://github.com/CU-ADCL/SDAPOMDPs.jl.git
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```
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### 3. Activate experiment environment
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In the SDAPOMDPs.jl directory execute the following command in the command-line to initialize the project:
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```bash

‎_includes/research.md‎

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This research aims to expand the algorithmic capability for tasking sensors to investigate human-specified hypotheses about space objects (SOs).
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The goal is to improve the ability to evaluate internal- and physical- state hypotheses in cases where there are many objects and a collection of sensors with diverse capabilities.
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**Problem Description**
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Describe the problem of catalog maintenance and hypothesis resolution
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<!-- **Problem Description** -->
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<!-- Describe the problem of catalog maintenance and hypothesis resolution -->
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**Technical Approach**
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Describe our technical approach:
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1. Generating a base plan using ILP
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2. Plan only over the OOI, where an action is a change in the plan
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The approach can be broken down into two main steps:
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1. Generating a base plan using integer linear programming
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2. Generating a refined MCTS plan accounting for the object of interest
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### 1) Integer Linear Program
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The base integer linear programming approach aims to judiciously allocate sensors to space objects in a manner where the severity of the worst-case scenario is minimized.
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Formally, the ILP is given by
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<script type="text/javascript" src="https://cdn.jsdelivr.net/npm/mathjax@3/es5/tex-mml-chtml.js"></script>
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$$
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\begin{aligned}
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\text{maximize} \quad & t \\
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\text{subject to} \quad & X_{ijt} \in \{0,1\}^{I\times J \times T} \\
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& X_{ijt} \preceq O \\
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& t \preceq \sum_{j,t} X_{ijt} \\
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& \sum_{i} X_{ijt} \preceq 1 \, .
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\end{aligned}
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$$
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Here $$X_{ijt}$$ is a binary 3-dimensional control variable representing whether or not observer $$j$$ observers object $$i$$ at time step $$t$$, and $$O_{ijt}$$ represents whether or not observer $$j$$ *is able to* observe object $$i$$ at time $$t$$.
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For ground based-sensors, the ILP plan can be visualized as follows:
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![ILP-Plan](../assets/images/ilp-plan-600.gif)
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.
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### 2) Monte Carlo Tree Search
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Building on the ILP solution as a baseline, we assume the existence of an object of interest in the catalogue, for which we seek to resolve a specific hypothesis. This work focuses on determining the drag configuration for the object in question. To achieve this, we use Monte Carlo Tree Search (MCTS) applied to a belief Markov Decision Process (MDP). The goal of the MCTS solver is to minimize the entropy of the distribution over possible hypotheses while minimally disrupting the baseline catalogue maintenance plan.

‎assets/images/ilp-plan-600.gif‎

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‎assets/images/ilp-plan.gif‎

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