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RunCode.md

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@@ -21,8 +21,8 @@ Installation, updating and testing are performed in [Julia's `pkg>` mode](https:
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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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