輪詢系統是依據事先訂定的拜訪方式和服務規則，透過一個伺服器來進行服務的多重佇列系統。典型的服務規則有五種：耗盡式、閘道式、限制式、k-限制式與時間限制式。每個服務規則表示一個決定策略來達成輪詢系統的特定性能，例如平均的等待時間。對於一個G/G/1/K輪詢系統，我們將集中於探討如何找出最佳的k-限制式服務規則之限制值。既然很難以數學解析的方式對現有的服務規則得到性能評估，實際上有必要針對G/G/1/K輪詢系統設計一個可以獲得更好系統性能之服務規則的方法。要達成一個實用可行的G/G/1/K輪詢系統，可以規劃為一個最佳化的問題，從而選擇適當的k-限制式服務規則來使平均等待的成本達到最小。首先，建立G/G/1/K輪詢系統之模型並形成隨機模擬最佳化的問題。接著，利用序的最佳化方法來求解一個足夠好的k-限制式服務規則，使得操作系統的期望成本能夠最小。最後將我們方法所得到的結果與其他的服務規則進行比較，發現我們方法的表現的確超越其他方法。

Polling systems are multi-queue systems served by a single server according to a prescribed visiting scheme and service discipline. There are five typical service disciplines: exhaustive, gated, limited, k-limited and time-limited. Each service discipline represents a decision strategy to achieve a certain performance of the polling system, for example the mean waiting time. We will focus on the problem of finding the optimal service limits in a G/G/1/K polling system with the k-limited service discipline. Since it is hardly to get any analytical formula for evaluating the system's performance using the existing service discipline, it would be more practical to design a service discipline that can obtain better system's performance for the G/G/1/K polling system. To accommodate a more realistic G/G/1/K polling system, we need to formulate an optimization problem and choose the most beneficial k-limited service discipline as the decision variable to optimize, say, the mean waiting cost for the polling system. First, we model the G/G/1/K polling systems and formulate as a stochastic simulation optimization problem. In addition, we apply the proposed ordinal optimization algorithm to G/G/1/K polling systems to solve for a good enough k-limited service discipline to minimize the expected cost of operating the system. We have compared our results with those obtained by the existing service disciplines and found that our approach outperforms the existing ones.