Zhongzhu Liu

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The energy of a graph is defined as the sum of the absolute values of all the eigenvalues of the graph. Let B(n) be the class of bipartite bicyclic graphs on n vertices containing a cycle with length congruent to 2 modulo 4. We determine respectively the graphs with minimal energies in the class of graphs in B(n) with exactly three cycles, in the class of(More)
Microarray experiments examine the change in transcript levels of tens of thousands of genes simultaneously. To derive meaningful data, biologists investigate the response of genes within specific pathways. Pathways are comprised of genes that interact to carry out a particular biological function. Existing methods for analyzing pathways focus on detecting(More)
Let G be a simple connected graph. The eccentric connectivity index ξ c(G) of G is defined as ξ c(G) = ∑ v∈V (G) d(v)ecG(v), where the eccentricity ecG(v) is the largest distance between v and any other vertex u ofG. In this paper, we obtain lower bounds on ξ c(G) in terms of the number of edges among n-vertex connected graphs with given diameter. Over(More)
Accurate thickness measurement of thin layer material is usually difficult in ultrasonic nondestructive evaluation (NDE), because the reflected ultrasonic echoes often overlapped which makes it difficult to separate these echoes and get the arrival times accurately. This paper used improved space alternating generalized expectation maximization (SAGE)(More)
When detecting the strain with passive wireless SAW (Surface Acoustic Wave) resonator sensor, the response signal is of narrow band, high frequency, low SNR and transient attenuation. The response signal is produced only in the case that the interrogation covers the operational frequency band of the SAW resonator. Burst of sinusoidal is used in the(More)
Ultrasonic echoes reflected from the inspected object contain information relative to the location, size and characteristics of defects. Accurate estimation of the echoes parameters is important in ultrasonic nondestructive evaluation (NDE). Model based method is often used to estimate ultrasonic echo signals, which models ultrasonic backscattered signal as(More)
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