比特幣是一種全球通用的加密電子貨幣，也是一種對等網路支付系統，是一種由用戶們完全自治的交易工具。比特幣經由一種稱為「挖礦」的過程產生，參與者透過處理交易驗證和記錄來獲取作為手續費的比特幣或是取得新產出的比特幣。
　　比特幣的挖礦是用戶透過解決具有一定運算工作量的工作量證明機制問題，來確認交易和防止雙重支付，管理比特幣網路。但原有的工作量證明機制所計算出來的結果是沒有意義的，而比特幣的崛起，使得越來越多的用戶加入挖礦的行列，導致更多的運算資源浪費在計算無意義的結果。若能夠整合這些挖礦的運算資源，來解決一些需要有意義且需要大量運算的問題，會是相當可觀的計算能力。
　　在本篇論文，我們提出與實現一個可在對等網路上有效益地執行計算任務之工作量證明演算法。應用工作量證明機制結合基因演算法，讓用戶在進行挖礦的過程中，可以利用基因演算法解決NP問題這類需要大量運算的問題。並且將此演算法實作並且整合至比特幣系統，讓用戶可以藉由解決NP問題來獲得獎勵，使得整個系統形成一個市場，利用對等網路的優勢，提供一個以基因演算法為基礎的平台，來解決大量運算的問題。

Bitcoin is a universal crypto currency and a peer-to-peer payment system. Online payments can be sent directly from one party to another without going through a financial institution. “Mining” is a process to generate bitcoin, users offer their computing power to verify and record payments to reward transaction fees and newly created bitcoin.
Mining of bitcoin is to solve proof of work puzzles that users need to expend a certain amount of computational capability to verify payments and prevent double-spending to manage the bitcoin network. However, the results of proof of work puzzles are meaningless values. With the rise of bitcoin, more and more computers join to mining bitcoin. Large amount of computational capability are wasted to compute the meaningless results. If we can integrate and use the computational capability of mining bitcoin to solve hard computational problems, the computational capability will be not considered wasteful but practical.
In this paper, we propose and implement an economic proof-of-work based algorithm which combines proof of work mechanism and genetic algorithm in a peer-servicing network. Genetic algorithm is used to solve NP problems in mining process. Integrating the implementation of proof of assignment into bitcoin system, users can reward incentives by solving NP problems. With the advantages of peer-servicing network, the whole system will become a market serves as a computing platform for solving hard computational problems using genetic algorithm.

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