111 research outputs found
Approximation algorithms for mobile multi-agent sensing problem
ํ์๋
ผ๋ฌธ (์์ฌ) -- ์์ธ๋ํ๊ต ๋ํ์ : ๊ณต๊ณผ๋ํ ์ฐ์
๊ณตํ๊ณผ, 2020. 8. ๋ฌธ์ผ๊ฒฝ.Multi-agent systems are generally applicable in a wide diversity of domains, such as robot engineering, computer science, the military, and smart cities. In particular, the mobile multi-agent sensing problem can be defined as a problem of detecting events occurring in a large number of nodes using moving agents. In this thesis, we introduce a mobile multi-agent sensing problem and present a mathematical formulation. The model can be represented as a submodular maximization problem under a partition matroid constraint, which is NP-hard in general. The optimal solution of the model can be considered computationally intractable. Therefore, we propose two approximation algorithms based on the greedy approach, which are global greedy and sequential greedy algorithms, respectively. We present new approximation ratios of the sequential greedy algorithm and prove tightness of the ratios. Moreover, we show that the sequential greedy algorithm is competitive with the global greedy algorithm and has advantages of computation times. Finally, we demonstrate the performances of our results through numerical experiments.๋ค์ค ์์ด์ ํธ ์์คํ
์ ์ผ๋ฐ์ ์ผ๋ก ๋ก๋ด ๊ณตํ, ์ปดํจํฐ ๊ณผํ, ๊ตฐ์ฌ ๋ฐ ์ค๋งํธ ๋์์ ๊ฐ์ ๋ค์ํ ๋ถ์ผ์ ์ ์ฉํ ์ ์๋ค. ํนํ, ๋ชจ๋ฐ์ผ ๋ค์ค ์์ด์ ํธ ๊ฐ์ง ๋ฌธ์ ๋ ์์ง์ด๋ ์์ด์ ํธ๋ฅผ ์ด์ฉํด ๋ง์ ์์ ๋
ธ๋์์ ๋ฐ์ํ๋ ์ด๋ฒคํธ๋ฅผ ๊ฐ์งํ๋ ๋ฌธ์ ๋ก ์ ์ํ ์ ์๋ค. ๋ณธ ๋
ผ๋ฌธ์์๋ ๋ชจ๋ฐ์ผ ๋ค์ค ์์ด์ ํธ ๊ฐ์ง ๋ฌธ์ ์ ์ํ์ ๊ณต์์ ์ ์ํ๋ค. ์ด ๋ฌธ์ ๋ ์ผ๋ฐ์ ์ผ๋ก NP-๋ํด ๋ฌธ์ ์ธ ๋ถํ ๋งคํธ๋ก์ด๋ ์ ์ฝ ํ์์ ํ์ ๋ชจ๋ ํจ์์ ์ต๋ํ ๋ฌธ์ ๋ก ํํํ ์ ์๋ค. ๋ฌธ์ ์ ์ต์ ํด๋ ์
๋ ฅ ๋ฐ์ดํฐ์ ํฌ๊ธฐ๊ฐ ์ปค์ง์๋ก ๋ณดํต ํฉ๋ฆฌ์ ์ธ ์๊ฐ ์ด๋ด์ ๊ณ์ฐํ๊ธฐ ์ด๋ ต๋ค. ๋ฐ๋ผ์ ๋ณธ ๋
ผ๋ฌธ์์๋ ํ์์ ์ ๊ทผ ๋ฐฉ์์ ๊ธฐ์ดํ ๋ ๊ฐ์ง ๊ทผ์ฌ ์๊ณ ๋ฆฌ์ฆ (์ ์ญ ํ์ ์๊ณ ๋ฆฌ์ฆ, ์์ฐจ ํ์ ์๊ณ ๋ฆฌ์ฆ)์ ์ ์ํ๋ค. ๋ํ, ์์ฐจ ํ์ ์๊ณ ๋ฆฌ์ฆ์ ์๋ก์ด ๊ทผ์ฌ ๋น์จ์ ์ฆ๋ช
ํ๊ณ ๊ทผ์ฌ ๋น์จ์ ์ ํํ๊ฒ ์ผ์นํ๋ ์ธ์คํด์ค๋ฅผ ์ ์ํ๋ค. ๋ํ, ์์น ์คํ ๊ฒฐ๊ณผ๋ก ์์ฐจ ํ์ ์๊ณ ๋ฆฌ์ฆ์ ํจ๊ณผ์ ์ธ ํด๋ฅผ ์ฐพ์์ค ๋ฟ ์๋๋ผ, ์ ์ญ ํ์ ์๊ณ ๋ฆฌ์ฆ๊ณผ ๋น๊ตํด ๊ณ์ฐ ์๊ฐ์ ์ด์ ์ ๊ฐ์ง๊ณ ์์์ ํ์ธํ๋ค.Chapter 1 Introduction 1
Chapter 2 Literature Review 4
Chapter 3 Problem statement 7
Chapter 4 Algorithms and approximation ratios 11
Chapter 5 Computational Experiments 22
Chapter 6 Conclusions 30
Bibliography 31
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