本論文討論型 I混合設限於某一定應力的加速壽命試驗。所使用的模型是具有一般性的對數位置尺度壽命分佈，其平均壽命和應力的關係是呈現一個線性關係, 而尺度變數是一個常數。我們利用最大概似法求得參數估計, 並且推導出期望費雪信息矩陣, 進而求得參數最大概似估計的近似變異數。此外, 我們利用模擬計算觀測費雪信息矩陣, 並且發現其值與所推導的期望費雪信息矩陣是一致。 
最後，在成本限制條件下，我們討論最佳化設計。亦即，在無加應力情況下，我們想找出最適當的樣本個數、失敗個數、以及檢測時間的配置使得所估計的第p個百分位數的一般訊息為最大。

In this paper, we consider a constant stress accelerated life tests terminated by a hybrid Type-I censoring regime at one of the stress levels.  A model based on a general log-location-scale lifetime distribution with mean life which is a linear function of stress, along with constant scale, is discussed. The exact expectations associated with the likelihood function for the asymptotically valid variances of maximum likelihood estimates of model parameters are derived. The agreement with observed counterparts for finite samples in simulation study is also assessed. Finally, under the constraint that the total experimental cost does not exceed a pre-specified budget, the design yields better estimate of 100p-th percentile at normal operating condition is obtained.

1 Introduction 1
2 Assumptions and Model Description 2
3 Maximum Likelihood Estimation 3
4 Particle Swarm Optimization 5
5 Simulation Study 7
6 Optimal Test Plan 7
7 CONCLUDING REMARKS 10
Appendix 14
References 16

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