建構銷售與作業規劃決策支援系統之研究

The Construction of Decision Support Systems of Sales and Operations Planning with the Integration of Material and Financial Flows

王俊中(Jun-Zhong Wang)

指導教授 ： 許秉瑜

國立中央大學/管理學院/企業管理學系/博士(2011年)

摘要

隨著企業規模擴大，供應鏈產銷整合的問題將變得更為複雜，產銷活動順暢與否一直是公司面臨的重要課題之一，如果出貨能力不足，會導致客戶抱怨，進而流失訂單；若貨品庫存量太多，公司會增加資金壓力，讓公司有高的風險虧損，因此在分派公司可用資源的決策考量過程中，往往需要許多不同決策情境試算來輔助產銷計畫的擬定。然而一個公司的產品動輒有數百項，實務上的做法多是由規劃人員自行經由Excel試算表輔以VBA巨集調整出各產品的生產數量與存貨水準，從管理的角度來看，此種方式雖能決定出可行的產銷計畫，但會有如下的問題所在: (1) 因人力有限，往往一個人只能顧及到某幾種產品，加上實務上多以規劃人員的經驗為主，故亦無標準的規劃方式，因此往往所產出的計畫多為可行解而非最佳解；(2) 目前的規劃方式多根據單一部門的角度來估算，無法擬定出多種資源限制下的計畫，而所擬定的計畫多未考慮到財務面的因素，像是應收帳款與應付帳款時間差所造成的現金水位缺口，會造成採購上的困難。
目前企業的ERP系統對供應鏈產銷整合多在資料處理的範疇，通常不牽涉到營運規劃的部分，對企業管理者制訂產銷計畫的決策支援有限。本研究在供應鏈網路環境下，考量短期財務規劃與中期生產規劃決策因素，以供應鏈整體營運資源整合分配的觀點，運用最佳化理論與資料倉儲技術，發展出銷售與作業規劃(Sales and operations planning, S&OP)所需的資料模型與決策模型以解決跨國供應鏈產銷多期多廠問題。本研究的貢獻包括：(1) 從ERP系統模組中找出與生產面及財務面相關之主營運資料(Master Data)欄位，並定義出多維度資料模型；(2) 根據資料模型定義出銷售與作業規劃所需的參數與變數，並在多規劃期多產品的四階供應鏈下，考量產能限制、生產技術限制、配送前置時間與應收應付帳款前置時間等特性建立一個以利潤極大化為績效目標的最佳化決策模型，此模型之產出結果包含建議之採購計畫、生產計畫、存貨計畫與配銷計畫；(3) 考慮到模型於實務應用時會有NP-Complete的問題，本研究提出了啟發式演算法，作為替代方案，之後並以不同的實驗情境比較來驗證求解的品質與效率。
最後為說明提出的模型如何應用，本研究考量企業本身營運狀況及實際運作上可能會面臨的環境選取來情境因子並進行實驗設計以測試不同的情境，訪談之後以產能負荷及、需求波動、製造成本及物流成本四個因子進行高低兩水準的四因子實驗設計，由測試的情境規劃結果可知，本研究所提出的方法論除了兼顧理論與實務，更以決策支援系統觀點從物流、金流與資訊流整合角度來處理問題，在實務應用上對企業應有所幫助。

關鍵字

供應鏈最佳化 ； 數學規劃 ； 演算法 ； 短期財務規劃 ； 中期生產規劃

並列摘要

Sales and operations planning (S&OP) focus on balancing between supply and demand in a company. It is utilized to ensure the alignment of plans supporting the business strategic goal. To compete production globally and utilizing resources spread several continents, many companies pay special attention to supply chain management. The planning scope can be characterized by three types of flows: The forward material flow that integrates the functions of procurement, production, distribution and sales to satisfy the end customer demands, and the backward information flow that allows each member on the chain to effectively acquire and share data from downstream members. The last type is financial flow. The financial flows operations have many impacts on material flows. When a company has to make capacity allocation between two customer demands, the fact of selecting one has an impact on material flow because payables and receivables frequently influences the inbound and outbound activities.
The aim of our research is to fill in the gap of S&OP in financial planning by presenting a decision model combining material flows and financial flows. The model integrates payment terms, processing times, costs, and prices to make a corporate plan should be executed to optimize business profits subject to budget and capacity. The paper proposes a decision support tool by integrating data model of data warehouse and mathematical model for optimization of S&OP in a company supply chain. To explore the applicability of the present study, a numerical example is considered to determine the sales and operations planning for the decision variables and profit of the company.

並列關鍵字

Supply chain optimization ； Mathematical planning ； Mid-term supply chain planning ； Short-term financial planning

參考文獻

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