dissertation 英音：[,disə'teiʃən] 美音：[,dɪsɚ'teʃən]
n.演讲； 一般指博士论文；论文
eg.
Ann did her dissertation on Baudelaire.
安做有关波德莱尔的博士论文。
A fascinating dissertation by Dr. Timothy Leary.
蒂莫西•利里博士所作的引人人胜的学术演讲。
In the final part, this dissertation gives two examples of railway line safety assessment, testifies the effectiveness
of the method and the model.
最后，在此基础上，本文对铁路线路安全评价做了实例说明，验证了本文所提出方法及模型的有效性。
thesis 英音：['θi:sis]
美音：['θisɪs] n. 论文；论点（学士学位或硕士学位候选人撰写的论文）
eg.
Over the years he returned several times to the city, first to complete a masters degree,
writing a thesis on Mecca and the Haj cities.
后来他多次回来，并在这里完成了硕士学位，他的论文主题是关于麦加和圣城。
Their thesis is that lipids (the group of molecules that includes fats), which are needed in small amounts to make
cell membranes, are toxic in larger quantities.
人体需要很少量的脂质（含脂肪的分子群）构成细胞膜，脂质过多是则有毒的，这是他们的论点。
paper英音：['peipə]美音：['pepɚ]
n. 论文（简报，报告之类的文章）牛津高阶英汉双解词典中的解释为：article
or essay, especially one read to an audience of academics or specialists 文章; （尤指）论文。
eg.
He read a paper at a medical conference on the results of his research.
他在医学会议上宣读了他的研究论文.
Can you spare some paper for me?
你能匀出一些纸给我吗?
What news is there in the papers this morning?
今天早上报纸里有点什么新闻?
This is a research paper.
这是一个研究报告。
treatise 英音：['tri:tis]美音：['tritɪs]
n.论文;专著[C][(+on/upon)（专题）论文.
eg.
柯林斯高级英语学习字典中的解释为：~ (on sth) a long and serious piece of writing on a particular subject。
韦氏词典中的解释为: a systematic exposition or argument in writing including a methodical
discussion of the facts and principles involved and conclusions reached。
eg.
The work at hand is not a theoretical treatise.
这本著作不是一篇理论性的论文。
另外 essay也有论文的意思：
essay 英音：['esei]
美音：['ɛse] n. 散文,随笔,小品文.(篇幅较短的论文)
eg.
At this stage, the image and character of the TV essay both served their purposes well then.
这个阶段的电视散文图像与文字已经各司其职了。
At this stage, the image and character of the TV essay both served their purposes well then.
这个阶段的电视散文图像与文字已经各司其职了。
Firstly, the essay discusses the related research of competence and competency model, including the building
method of competency model and the recruitment flow based on the competency model.
论文首先回顾了有关胜任素质和胜任素质模型的相关研究，总结了胜任素质模型的建立方法，并对基于胜任素质模型的招聘进行了阐述。
Students pay for one college credit. They must write an essay or keep a journal of their internship.
学生花钱来获得一学分。他们必须写一篇评论或者在实习期记全程日记