講座主題：New bounds on Majority coloring of digraph
專家姓名：蔡建生
工作單位：濰坊學(xué)院
講座時(shí)間：2023年6月24日 15:30-16:30
講座地點(diǎn)：數(shù)學(xué)院大會(huì)議室
主辦單位：煙臺(tái)大學(xué)數(shù)學(xué)與信息科學(xué)學(xué)院
內(nèi)容摘要：
A majority k-coloring of a digraph D with k colors is an assignment c:V(D)→ {1,2,……,k}, such that for every v, we have c(w)=c(v) for at most half of all out-neighbors w of v. Kreutzer et al. conjectured that every digraph admits a majority 3-coloring. For a natural number k, a 1/k-majority coloring of a digraph is a coloring of the vertices such that each vertex receives the same color as at most a 1/k proportion of its out-neighbours. Girao et al. conjectured that every digraph admits a 1/k -majority (2k-1)-coloring. In this paper, we prove that Kreutzer's conjecture is true for digraphs under some conditions, which improves Kreutzer's results. Moreover, we discuss the majority 3-coloring of random digraph with some conditions.
主講人介紹：
蔡建生，理學(xué)博士,，現(xiàn)任濰坊學(xué)院數(shù)學(xué)與信息科學(xué)學(xué)院教授,、中國(guó)工業(yè)與應(yīng)用數(shù)學(xué)學(xué)會(huì)圖論組合及應(yīng)用專業(yè)委員會(huì)常務(wù)委員,、中國(guó)工業(yè)與應(yīng)用數(shù)學(xué)學(xué)會(huì)信息和通訊領(lǐng)域的數(shù)學(xué)專業(yè)委員會(huì)委員,、山東數(shù)學(xué)會(huì)高等數(shù)學(xué)專業(yè)委員會(huì)常務(wù)理事,、山東師范大學(xué)和濟(jì)南大學(xué)碩士生導(dǎo)師,。,，發(fā)表相關(guān)學(xué)術(shù)論文60余篇,，出版學(xué)術(shù)專著1部,，2016年以來主持國(guó)家自然科學(xué)基金面上項(xiàng)目2項(xiàng)，主持山東省自然科學(xué)基金面上項(xiàng)目2項(xiàng),。主持完成的研究成果獲山東省自然科學(xué)三等獎(jiǎng)1項(xiàng),、山東省高校優(yōu)秀科研成果獎(jiǎng)2項(xiàng)，2021年獲得濰坊市五一勞動(dòng)獎(jiǎng)?wù)隆?/p>
