隨著深度學習的快速發展，如今深度學習已被廣泛的應用在各個領域，理所當然地也被應用於各種推薦系統中。推薦系統的主要目的是幫助用戶過濾大量信息，並提供滿足用戶個人喜好的產品或服務推薦，而隨者網路與電子設備的日益蓬勃發展所提供的便利性，使用者對於各種網路平台的依賴性也日漸提高，不論是電子商務平台或是音樂串流服務，推薦系統都已被廣泛地應用於其中，以提供用戶感興趣的項目來延長使用者的停留時間或是更多消費。本論文以最先進的推薦系統框架RNNCF（“以循環神經網路為基礎之協同過濾推薦系統”的縮寫）為主要研究對像，提出了幾種新的帶有更多時間資訊的訓練資料格式，同時也將最先進的激活函數SELU（“縮放指數線性單元”的縮寫）引入RNNCF，研究應用此激活函數在不同網路階段所造成的影響。最後，我們在兩個真實世界資料集MovieLens-1m 與 Pinterest 上進行了實驗，結果表明，與LSTM相比，將SELU引入RNNCF的MLP具有更高的收益。

As the rapid development of deep learning, deep learning has been widely used in various fields, and also used in various recommendation systems. The main purpose of the recommendation system is to help users filter a large amount of information and provide product or service recommendations that meet the user's personal preferences. The convenience provided by the growing of the Internet and electronic devices makes users reinforce dependence on various network platforms. Whether it is an e-commerce platform or a music streaming service, recommendation systems have been widely used to provide the item that users interest in to extend the user's stay time or more consumption. In this paper, we use a state-of-the-art recommendation system framework, the Recurrent Neural Network based Collaborative Filtering Recommender System (RNNCF), as the main study theme, and propose few new training data formats with more time information inside. At the same time, we also introduce the state-of-the-art Scaling Exponential Linear Unit (SELU) activation function, into the RNNCF to study the impact of applying this activation function in different network stages. Finally, we conduct the experiments on two real-world datasets, MovieLens-1m and Pinterest, and the results show that compared with the Long Short-Term Memory (LSTM), using the SELU as the activation function in the Multi-Layer Perceptron (MLP) from the RNNCF has higher benefits.

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