在本篇論文中，給定一個圖形G以及一個非負整數h，而h-限制連通度
是指在G中的一個最小基數點集合，假使存在這個點集合，從圖G中移除，
使圖G會產生出許多連通圖，而每一個在連通圖內的點都必須滿足分枝度
(degree) 至少為h，這個h-限制連通度是一個通用且典型的連通度
(connectivity)性質，並且針對現今的大型多處理器系統提供可靠度以及容錯(fault-tolerance)標準。接下來介紹局部雙扭超立方體(locally twisted cubes)，在建構多處理器系統中，是一個大眾廣泛所知的網路拓墣結構，可被標示為LTQn。在本篇論文中，我們首先證明局部雙扭超立方體的2-限制連通度等於4n−8當n≥4，而後面接著證明3-限制連通度等於8n−24當n≥5。

Give a graph G and non-negative integer h, the h-restricted connectivity of G is the minimum cardinality of a set of nodes in G, if exists, whose deletion disconnects G and the degree of each node in every remaining component is at least h. The h-restricted
connectivity is a generalization of the classical connectivity and can provide more accurate measures for the reliability or fault-tolerance of multiprocessor system. The n-dimensional locally twisted cubes, denoted by LTQn, is a well-know network topology for building
multiprocessor systems.
In this paper, we first show that 2-restricted connectivity of the n-dimensional locally twisted cubes is 4n-8 for n≥4, and show that 3-restricted
connectivity is equal to 8n-24 for n≥5.

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