應(yīng)yl7703永利官網(wǎng)張和平教授和徐守軍教授邀請，南開大學(xué)數(shù)數(shù)學(xué)科學(xué)學(xué)院李佳傲老師將于2020年9月2日進(jìn)行線上學(xué)術(shù)報告。

報 告：Nowhere-zero flows of signed graphs

時 間：9月2日下午3:40

地 點：騰訊會議, ID:445 319 208, 密碼:0902

摘 要：Parallel to Tutte's flow theory on ordinary graphs, Bouchet (1983) introduced a general flow theory for signed graphs, arising from the dual of local tension of graphs embedding on non-orientable surfaces. In contrast to Tutte's flow conjectures, Bouchet (1983) conjectured that every flow-admissible signed graph admits a nowhere-zero 6-flow. Bouchet himself proved that such signed graphs admit nowhere-zero 216-flows，and Zyka(1987) further improved to 30-flows. In this talk, we will present our recent work joint with DeVos, Lu, Luo, Zhang, Zhang (JCTB, 2020, online), showing that every flow-admissible signed graph admits a nowhere-zero 11-flow. We shall also discuss some related results and problems.

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報告人簡介

李佳傲，中國科學(xué)技術(shù)大學(xué)本科碩士，美國西弗吉尼亞大學(xué)博士。現(xiàn)任南開大學(xué)數(shù)學(xué)學(xué)院講師。主要研究興趣是圖論中的整數(shù)流問題，圖染色，網(wǎng)絡(luò)與組合優(yōu)化問題等。已完成和發(fā)表論文近二十篇，現(xiàn)主持國家自然科學(xué)基金青年項目和天津市自然基金青年項目各1項。

甘肅省應(yīng)用數(shù)學(xué)與復(fù)雜系統(tǒng)重點實驗室

yl7703永利官網(wǎng)

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