在現今的航空業中，機場間的飛航頻率涉及市場佔有及成本考量，是公司彼此競爭的重要因素。而隨著市場蓬勃發展，航空公司間的商業關係也從單純地互相競爭發展出策略結盟與合作協議。在眾多合作策略中又以代碼共享尤為關鍵。
代碼共享作為航空公司間的一種買位機制，可以讓原本沒有經營某航段的公司藉由商業協議參與該航段的經營，或讓經營某航段的公司視利益分配及成本考量由他人代飛，常見於用以接駁長途航班的中轉站或少數頻次密集的短途航班。據統計，在美國市場有逾半數的航空公司有採取代碼共享的策略，且在熱門樞紐機場附近的航線尤為盛行。
有別於其實際在業界的盛行，據悉目前尚未有嚴格的量化模型同時考慮代碼共享策略與飛航頻率競爭。有鑑於其重要性，本文試圖以探討頻率競爭的混整數賽局為基礎，建立一個涵蓋代碼共享策略的模型。經由量化計算求解各航線之最優頻率，並可對航空公司間代碼共享的合作與否及合作對象、利潤分配提出策略建議。
透過數值實驗，我們從模型收益的比較中肯定了代碼共享機制對於航空公司增加營收帶來的正面效益，同時也增進乘客的福祉。且以一段航程為例，對航空公司處在不同利潤配下的決策情形做出了綜合的分析及建議。
最後，受限於問題的複雜性，設計更完善的模型及探討數值結果的深層意義將是未來持續改進的方向。

In the contemporary aviation industry, determining flight frequencies between airports entails careful consideration of market share and costs, playing a vital role in the competitive landscape among airlines. As the aviation market continues to flourish, the nature of commercial relationships among airlines has evolved from mere competition to the establishment of alliances and collaborations. Among various cooperative strategies, the code-sharing agreement stands out as a particularly crucial approach.
As a mechanism facilitating seat sales among airlines, code-sharing enables airlines without operational control over a specific flight segment to participate in its operation through commercial agreements. It is commonly employed at hub airports for facilitating connections between long-haul flights or high-frequency short-haul flights. Statistics reveal that over half of the airlines in the U.S. market have adopted code-sharing strategies, particularly prevalent on routes adjacent to popular hub airports.
Despite its widespread implementation in the industry, it is noteworthy that there is currently no comprehensive quantitative model that simultaneously considers code-sharing strategies and flight frequency competition. Recognizing its significance, this research aims to construct a model encompassing code-sharing strategies within the framework of mixed integer game theory for frequency competition. The proposed model utilizes quantitative calculations to determine the optimal frequency for each flight segment and offers strategic insights on the decision to engage in code-sharing, suitable cooperating partners, and profit distribution among airlines.
Through numerical experiments, we have affirmed, in a scholarly manner, the positive impact of a code-sharing mechanism on increasing revenue for airlines and enhancing passenger well-being. Additionally, we have conducted a comprehensive analysis and provided recommendations for decision-making for airlines under varying profit-sharing schemes, using a specific flight segment as an example.
In conclusion, due to the complexity of the problem, the direction for future continuous improvement lies in the design of more refined models and exploring the underlying significance of the numerical results.

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