無線感測網路(Wireless Sensor Networks, WSNs)是由數個低成本且體積小的無線感測器 (Sensor)所組成，其生命週期往往受限於每個感測器的電力，故維持網路壽命是探討無線感測網路很重要的一項議題。無線感測網路應用範圍很廣，包括農業動植物監控、醫療與健康照護、智慧生活、軍事用途、綠色節能等。近年來，隨著無線充電技術的逐漸成熟，藉由移動裝置進行充電以延長無線感測網路壽命的研究也越來越受多，行動充電車可近距離的替感測器進行無線充電，延長感測器電力壽命。如何在利用無線感測網路監測環境的同時，不讓感測器因能量消耗殆盡而造成無線感測網路中斷，是當前最主要探討的議題，因此，在此論文中，我們研究在無線感測網路環境中如何同時考量移動裝置的耗電量及維持無線感測網路生命下，在降低時間複雜度下計算出移動裝置之充電路徑，使無線感測網路能持續不間斷地運作。

Although wireless sensor devices usually have limited power, they are widely deployed in various applications, such as in remote sensing for forestry applications, military monitoring, and animal behavior. Most sensor applications deploy sensor devices in natural environments, such as forests, tunnels, and caves, to monitor targets and to collect data. To permanently monitor target environments, the battery in a sensor device needs to be recharged as its battery capacity the limited. A Wireless Charging Vehicle (WCV) uses wireless charging technology to prolong the lifetime of sensor network applications by recharging the device's battery. The WCV is usually equipped with a large capacity battery, an electromagnetic field, and wheels such that it can move throughout an entire sensor network to charge sensors' batteries. When the WCV does not need to recharge any sensor's battery, it stays at a service station to recharge its own battery. Hence, a WCV needs to consider two things: sensor network lifetime, and vehicle energy consumption. This work proposes a geometric solution called the Dynamic Path Generation Scheme (DPG-Scheme) to arrange the Wireless Charging Vehicle's travelling path while minimizing a vehicle's energy consumption and maximizing a sensor network's lifetime. The DPG-Scheme is based on the space-filling curve solution. Based on the properties of the space-filling curve, the DPG-Scheme uses space-filling curves as a space-filling curve heuristic for the NP-hard Euclidean travelling salesperson problem. The DPG-Scheme can reduce computational time when computing a wireless sensor network's (WSN's) travelling path and a new path is calculated rapidly during sensor network topology changes.

Chinese Abstract
Abstract
Acknowledgement
Chapter 1 Introduction
1.1 Background
1.2 Problem Description
1.3 Main Contribution
1.4 Thesis Organization
Chapter 2 System Background
2.1 A Survey of Mobile Charger in WSN
2.2 Motivation
Chapter 3 High Performance and Energy-Efficient Routing Algorithms
3.1 Problem Formulation
3.2 Dynamic Path Generation Scheme in Mobile Charger
3.3 Analysis of Dynamic Path Generation Scheme
Chapter 4 Simulations
4.1 Definitions of Parameters in Simulation
4.2 Simulation Results
Chapter 5 Conclusion
References

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