Approximating the chromatic index of multigraphs

It is well known that if G is a multigraph then χ′(G)≥χ′^*(G):=max {Δ(G),Γ(G)}, where χ′(G) is the chromatic index of G, χ′^*(G) is the fractional chromatic index of G, Δ(G) is the maximum degree of G, and Γ(G)=max {2|E(G[U])|/(|U|−1):U⊆V(G),|U|≥3, |U| is odd}. The conjecture that χ′(G)≤max {Δ(G)+1,⌈Γ(G)⌉} was made independently by Goldberg (Discret. Anal. 23:3–7, 1973), Anderson (Math. Scand. 40:161–175, 1977), and Seymour (Proc. Lond. Math. Soc. 38:423–460, 1979). Using a probabilistic argument Kahn showed that for any c>0 there exists D>0 such that χ′(G)≤χ′^*(G)+c χ′^*(G) when χ′^*(G)>D. Nishizeki and Kashiwagi proved this conjecture for multigraphs G with χ′(G)>⌊(11Δ(G)+8)/10⌋; and Scheide recently improved this bound to χ′(G)>⌊(15Δ(G)+12)/14⌋. We prove this conjecture for multigraphs G with $\chi'(G)>\lfloor\Delta(G)+\sqrt{\Delta(G)/2}\rfloor$\chi'(G)>\lfloor\Delta(G)+\sqrt{\Delta(G)/2}\rfloor , improving the above mentioned results. As a consequence, for multigraphs G with $\chi'(G)>\Delta(G)+\sqrt {\Delta(G)/2}$\chi'(G)>\Delta(G)+\sqrt {\Delta(G)/2} the answer to a 1964 problem of Vizing is in the affirmative.     

民间借贷融资担保风险之法律研究

民间借贷担保是我国融资担保体系的重要组成部分之一。随着担保体系的逐步完善．其得以快速发展的同时也存在诸多法律风险。建立完善的法律制度体系,防范民间借贷融资担保的风险．可以使得融资担保的三方主体能够在良好法律机制的制约下得以互利发展。     

《三国演义》接受的文化阐释

《三国演义》[1]的创作是作者个人心理与民族文化心理的一种集大成,而本书的接受过程也是在文化语境中产生的,在接受过程中,虽然表现出来的形式多种多样,但在这纷繁复杂的表象之外,其实还是有些文化含义贯穿始终,本文择其要者加以论述,分别是强烈的政治教化功能,积极进取的入世精神,深重的忧患意识。     

回归分析在短跑教学中的应用

针对教学中学生100m跑的具体情况,采用逐步回归分析方法建立了回归方程;在此基础上,分别以各相关因素、100 m跑成绩作为因变量与自变量建立了多项式回归方程,并依据正态分布理论制定了各因素平衡发展的标准.上述方法在指导短跑教学中取得了较好的效果.     

Hui Muslim‐Han Chinese Differences in Perceptions on Endogamy in Urban China

Using a survey data set (n?=?1,992) collected in Lanzhou, China, I examine the Hui?–?Han differences in perceptions on intermarriage. The questions I ask in this paper include: What is the extent of interethnic marriages in Lanzhou? Do the Hui and Han feel differently about interethnic marriage? Which ethnic group is more negative about Hui?–?Han marriages and why? Are perceptions about endogamy patterned by ethnicity or socio-economic status or both? I seek plausible answers to these questions in this paper. A preliminary analysis of the 2001 survey data shows a high degree of endogamy in Lanzhou. It also shows that the Hui are more negative about intermarriage than the Han. However, the ethnic differences in perceptions on intermarriage fade away with socio-economic variables controlled.     

供给侧改革理念下我国旅游购物陷阱分析 ——基于利益分配链主体的博弈视角

旅游购物市场的购物陷阱一直是制约我国旅游业健康发展的重要问题,而作为利益链分配主体的旅游中介、旅游购物商店和旅游者的非均衡博弈是此类陷阱居高不下的主要原因.文章基于供给侧改革,运用博弈一般均衡分析和信息经济学理论,对旅游购物商店之间以及旅游中介和旅游者的博弈行为进行分析,最后就博弈产生的恶性价格竞争和代理成本问题提出诚信进化和旅游中介创新的相关建议.     

略论文征明的造园思想

文征明在中国造园史上占有较为重要的一席之地,他所主持设计的拙政园迄今为止仍然保留着一开始的主要风格和特点。这说明文征明的造园思想自有其高明之处。具体而言,在拙政园的营建过程中,文征明的总体思路可基本概括为因地制宜、法乎自然,除此之外,文征明更注重赋予自然景观一种个性化的人生理想和价值观,并由此彰显出明代江南文人的精神追求和独立意识。     

初唐的文学理解与文学观念的形成

初唐的文学创作与文学批评中存在着观念层次和实际存在空间的矛盾现象,即文人一方面汲汲于文事,一方面大力贬抑文学价值。这样的文学理解和文学观念是由魏征的政本思想逻辑塑造的。唐初士人普遍接受了贞观朝确立的为政本末价值体系,既盛饰文辞以求仕进,又刻意以摒弃雕虫、高扬器识为标榜,这正是初唐反拨六朝的时代语境和文人的生存处境使然。