We describe the irreducible components of the jet schemes with origin in the singular locus of a two-dimensional quasi-ordinary hypersurface singularity. A weighted graph is associated with these components and with their embedding dimensions and their codimensions in the jet schemes of the ambient space. We prove that the data of this weighted graph is equivalent to the data of the topological type of the singularity. We also determine a component of the jet schemes (equivalent to a divisorial valuation on $\mathbb{A}^{3}$), that computes the log-canonical threshold of the singularity embedded in $\mathbb{A}^{3}$. This provides us with pairs $X\subset \mathbb{A}^{3}$ whose log-canonical thresholds are not computed by monomial divisorial valuations. Note that for a pair $C\subset \mathbb{A}^{2}$, where $C$ is a plane curve, the log-canonical threshold is always computed by a monomial divisorial valuation (in suitable coordinates of $\mathbb{A}^{2}$).

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准普通表面奇点的 JET 方案

我们描述了射流方案的不可约分量，起源于二维准普通超曲面奇点的奇异轨迹。加权图与这些组件及其嵌入维度及其在环境空间的喷射方案中的余维度相关联。我们证明了这个加权图的数据等价于奇点拓扑类型的数据。我们还确定了喷气式飞机计划的一个组成部分（相当于对$\mathbb{A}^{3}$)，计算嵌入的奇点的对数规范阈值$\mathbb{A}^{3}$. 这为我们提供了对$X\子集 \mathbb{A}^{3}$其对数规范阈值不是通过单项除数估值计算的。请注意，对于一对$C\subset \mathbb{A}^{2}$， 在哪里$加元是一条平面曲线，对数规范阈值总是通过单项除数估值计算（在合适的坐标$\mathbb{A}^{2}$）。