為了避免產生無法繞線的配置，許多可繞性導向的擺放配置器採用全域繞線器來評估它們配置的結果，但是利用全域繞線器來評估一個配置會有以下幾個問題: (1) 全域繞線器會花很多的時間在一個很難被繞線的配置，(2) 因為考慮到時間，全域繞線器會粗略的去繞一個配置，這可能會使得評估這個配置的結果不準確，(3) 大部分的全域繞線器沒有考慮到時序的限制。
因此，這篇論文提出一個效率極高的無法繞線之配置的辨識器，其中包含了window-based 以及cutline-based這兩個方法。window-based 這個方法可以正確的辨識一個配置是否可以繞線並且可以指出一個配置的無法繞線的區域，以及可以回報一個配置它的全部溢出的下限值。如果考慮到時序的限制，cutline-based 的方法能夠偵測一個配置是否可以被繞線。實驗結果顯示window-based 的方法能夠找出23個現今常被使用的極難被繞線的全域繞線基準中的16個基準，當我們考慮時序的限制，cutline-based 的方法能夠顯示出很多個基準它是無法繞線。

Chapter 1 Introduction
Chapter 2 Preliminaries
2.1 Global Routing Problem
2.2 The Objective of This Thesis
Chapter 3 Window-based Unroutable Region Recgonition
3.1 Layout Scanning Algorithm
3.2 Window Dimension Determination
3.3 Lower Bound of Total Overflow Identification
Chapter 4 Cutline-based Unroutable Panel Recognition
Chapter 5 Experimental Results
5.1 Unroutable region recognition by different window dimensions
5.2 The parallelism of window-based unroutable region recognition
5.3 Effectiveness of the window dimension determination method
5.4 Lower bound of total overflow
5.5 Effectiveness of unroutable panel recognition
Conclusion
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