自2020年新冠肺炎爆發，人與人的接觸急遽下降，保持社交距離、戴口罩成為人們的日常，許多人轉而使用外帶、外送的方式，餐飲業的內用人數也急劇下降，而在這樣不僅餐廳難以宣傳經營理念，也無法完全排除人與人的接觸，食材供應商也因為餐廳需求減少，急需增加新的銷售通路。所幸，隨著資訊化、工業4.0相關的浪潮，科技上的發展已可在整合後應付這樣的需求，當中包含藉由科技的進步來方便消費者取得食物及其溯源資料。因此，如何在疫情的威脅下，建立一個可信賴的食品供應鏈信賴溯源系統並維持消費者的消費體驗成為本篇論文的主旨，而區塊鏈技術的特性可以協助達成。

本篇論文主要分為兩大面向。第一，創建一個新的商業模式降低人與人的接觸風險；第二，多面向的溯源體驗。商業模式上，我們與販賣機廠商合作，建立一個消費者可線上預訂、線下於販賣機(智販機)取貨並溯源的營運模式。而在溯源上，我們提供網頁及APP的溯源平台。另外，我們也處理仿冒的問題並同時增加與消費者的互動及田間紀錄功能等。

Since the outbreak of COVID-19, person-to-person contact has plummeted, and keeping social distance and wearing masks has become a daily routine for people. Many people have switched to takeout and delivery methods. The number of insiders in the catering industry has also plummeted. However, it is not only difficult for the restaurant to promote the business philosophy but also cannot completely exclude the contact between people. Food suppliers also urgently need to add new sales channels because of the reduced demand in restaurants. Fortunately, with the wave of information technology and Industry 4.0, the development of technology can meet such needs after integration, including the advancement of technology to facilitate consumers to get food and its traceability information. Therefore, how to establish a reliable food supply chain trust traceability system and maintain consumers’ consumption experience under the threat of the epidemic has become the major theme of this paper, and the characteristics of blockchain technology can help achieve.

We mainly divided this paper into two aspects. First, create a new business model to reduce the risk of person-to-person contact; second, a multi-faceted traceability experience. In terms of business model, we cooperate with vending machine manufacturers to establish a business model in which consumers can order online, pick up goods at vending machines (smart vending machines) offline, and trace the source. As for traceability, we provide a traceability platform for web and mobile applications. In addition, we also deal with the problem of counterfeiting and increase interaction with consumers and field record functions, etc.

Acknowledgements
Abstract......................................i
中文摘要......................................ii
1 Introduction................................1
2 Related Works...............................5
2.1 Blockchain................................5
2.1.1 Characteristics.........................6
2.2 Ethereum..................................8
2.2.1 Public Chain and Private Chain..........9
2.2.2 Smart Contract.........................10
2.2.3 Remix and Solidity.....................10
2.2.4 Eth 1.0 to Eth 2.0.....................11
2.3 IPFS.....................................12
2.3.1 Overview...............................12
2.3.2 Filecoin...............................12
2.3.3 IPFS Cases.............................13
2.4 Supply Chain Traceability................15
3 System Design..............................19
3.1 System Overview..........................19
3.1.1 Agchain Overview.......................19
3.1.2 iBENDOM Overview.......................20
3.2 Business Scenario........................21
3.2.1 Crops..................................22
3.2.2 E-commerce platform....................24
3.2.3 Other extension practical field........25
3.3 Back-end Server..........................27
3.3.1 Blockchain and Smart Contract Design...28
3.3.2 Database Design........................35
3.4 Traceability Service.....................36
3.4.1 Supply Chain Link......................37
3.4.2 Fake Prevent...........................38
3.4.3 Data Verification......................40
4 System Implementation......................41
4.1 Smart Contract...........................41
4.1.1 Overview...............................41
4.1.2 Ropsten Network and Infura.............42
4.1.3 Crop Index Contract....................44
4.1.4 Meal Box Ingredients Contract..........46
4.1.5 Meal Box Production Process Contract...47
4.1.6 Field Record Contract..................48
4.2 API Server...............................49
4.2.1 Node.js and Express....................50
4.2.2 web3.js................................51
4.2.3 Middleware.............................51
4.2.4 MVC pattern............................51
4.3 Front-end Web Structure and Function.....53
4.3.1 Overview...............................53
4.3.2 Functions..............................54
4.4 Front-end APP Structure and Function.....54
4.4.1 Overview...............................54
4.4.2 Functions..............................55
4.5 Traceability Service.....................57
4.5.1 Producer...............................58
4.5.2 Customer...............................61
4.5.3 Tracing Process........................63
5 Conclusion and Future Works................67
5.1 Conclusion...............................67
5.2 Future Works.............................68
References...................................71

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