隨著台灣高等教育全球化，學術研究領域的發展與貢獻成為評估國家經濟發展的重要指標之一，為了提升台灣各大學在全球高等教育的競爭力，教育部近幾年更加重視各大專院校的國際化程度，英語成為各大專院校發表學術研究成果的主要媒介。
然而，對英語為外語的學者而言，要以全英語撰寫研究成果並非易事，其英文寫作的訓練經常不足以獨自撰寫全英語的學術研究成果，而隨著網際網路的進步，配合功能強大的搜尋引擎，使得資訊的取得越來越容易，直接或間接地導致學者有意或無意地抄襲他人的想法。
由於許多學者對於抄襲的認知不正確，認為稍作修改內容就不算抄襲，並不知道自己已觸犯抄襲行為。然而，目前市面上抄襲偵測軟體其功能多為比對論文資料庫或網路資源，只能偵測出簡單的抄襲類型，且只有單純使用單一字詞為基礎進行比對，不但無法偵測文句改寫的現象，且無法教導學者如何適切的改寫句子等反抄襲方法。因此，我們更需主動協助或教育學者偵測所著文件是否抄襲。
有鑑於此，本研究將提出一個偵測方法能指引改寫句子期望改寫時不要犯下抄襲的行為，本偵測方法利用語法結構分析擷取句子中所有的片語，以片語為比對單位，改善單純使用單一字詞比對的準確性，並同時考量同義字替代及字詞次序的改變，計算句子的語意相似度及次序相似度。透過來源文件及使用者修改文件中句子的比對，找出可能有抄襲情形的改寫文件，並詳細分析其所使用的改寫手法，期望藉由分析結果，建議學者如何避免觸犯抄襲。
實驗結果發現本研究所提出的方法是可行的，實驗數據證實採用片語比對可改善傳統使用單一字詞的準確性，使用語意相似度也對結果有正面的影響。另外，結合PATH和WUP計算語意相似度，比單純使用PATH或WUP有較好的表現。

Along with globalization of higher education in Taiwan, the contribution and development of academic researches become one of national economic development indicators. In order to enhance the competitiveness of universities in Taiwan, Ministry of Education pay more attention to the degree of internationalization in recent years. As a result, English has become the main medium for universities to publish academic researches.
However, it is not an easy task for Taiwanese researchers─English as a foreign language learners─to compose a variety of writings in English. There is not enough English writing training for researchers to compose researches in English by themselves. With the advance of Internet, it is easier to obtain information using powerful search engines on the web. It leads researchers to copy the ideas of others intentionally or unintentionally.
In fact, many researchers’ recognition of plagiarism is incorrect. They think that it is not regarded as plagiarism when they modify the documents slightly, so they does not recognize their behavior is illegal. Nevertheless, the major function of the currently available plagiarism-detecting softwares which plays the role of checking possibly plagiarized papers with the essay database or Internet-based search engines. These existing systems can only detect simple kinds of plagiarism based on only single terms. It causes that the cases of paraphrase can not be detected, and systems are not able to guide researchers to paraphrase properly. Hence, there is a requirement of an environment which can help researchers and educate them detect whether their documents are plagiarized or not.
In this study, a new plagiarism detection method which can guide paraphasing the original sentences to avoid plagiarism will be proposed. The proposed method make use of the syntactical structure to retrieve all phrases of the sentences to improve the accuracy of using single terms. In addition, we considers the substitution and reversal of the terms, computing the semantic similarity and order similarity of the sentences. Find out the paraphrased documents which is suspected to avoid plagiarism through original document and user modified document. Finally, we are looking forward to suggest users how to avoid plagiarism.
After evaluation, the proposed method can improve the accuracy of using single term traditionally. The semantic similarity can also take an advantage of the results. Moreover, the performance of using PATH and WUP to calculate the semantic similarity is better than only using PATH or WUP.

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網站資料
The Comprehensive Perl Archive Network (CPAN)
http://search.cpan.org/
The Stanford NLP (Natural Language Processing) Group
http://nlp.stanford.edu/software/lex-parser.shtml
WordNet
http://wordnet.princeton.edu/
維基百科
http://www.wikipedia.org/