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On Jumped Wenger Graphs

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Communications in Mathematical Research 2022年第2期38卷 319-332页

作者： Li-Ping wang daqing wan Weiqiong wang Haiyan Zhou State Key Laboratory of Information Security Institute of Information EngineeringCASChina School of Cyber Security University of Chinese Academy of SciencesChina Department of Mathematics University of CaliforniaIrvineCAUSA School of Science Chan’an UniversityXi'anChina School of Mathematics Nanjing Normal UniversityNanjingChina

We introduce a new infinite class of bipartite graphs, called jumped Wenger graphs, which has a similar structure with Wenger graphs. We give a tight upper bound of the diameter for these graphs and the exact diameter... 详细信息

关键词： Wenger graphs diameter girth algebraic graph theory

On error distance of Reed-Solomon codes

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Science China Mathematics 2008年第11期51卷 1982-1988页

作者： LI YuJuan wan daqing Institute of Mathematics Chinese Academy of SciencesBeijing 100080China Department of Mathematics University of CaliforniaIrvineCA 92697-3875USA

The complexity of decoding the standard Reed-Solomon code is a well known open prob-lem in coding theory. The main problem is to compute the error distance of a received word. Using the Weil bound for character sum estimate, we show that the error distance can be determined precisely when the degree of the received word is small. As an application of our method, we give a significant improvement of the recent bound of Cheng-Murray on non-existence of deep holes (words with maximal error distance).

关键词： Reed-Solomon code error distance deep hole character sum

POLES OF ZETA FUNCTIONS OF COMPLETE INTERSECTIONS

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Chinese Annals of Mathematics,Series B 2000年第2期21卷 187-200页

作者： wan daqing(Department of Mathematics, University of California, Irvine, CA 92697-3875, USA.) Department of Mathematics University of California Irvine CA 92697-3875 USA

A vanishing theorem is proved for e-adic cohomology with compact support on an affine (singular) complete intersection. As an application, it is shown that for an affine complete intersection defined over a finite field of q elements, the reciprocal "poles" of the zeta function are always divisible by q as algebraic integers. A p-adic proof is also given, which leads to further q-divisibiliy of the poles or equivalently an improvement of the polar part of the AxKatz theorem for an affine complete intersection. Similar results hold for a projective complete intersection.

关键词：极点 ZETA函数完全交叉消没理论

A Preliminary Study on Mechanisms of Well Water Temperature Responses Based on the Modes of Stress Loading

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Earthquake Research in China 2011年第4期25卷 477-485页

作者： Chen daqing wan Yongfang Earthquake Administration of Guangdong Province Guangzhou 510070 China

Based on the studies of the predecessors, and contrasting the modes of stress loading with water level and water temperature response characteristics of a well-aquifer system, this paper draws a preliminary conclusion on the mechanisms of water temperature responses in a well caused by three modes of stress loading, i.e. gas escape, heat dispersion and cold water penetration mechanisms for elastic seismic wave stress loading; the fracture seepage mechanism for seismic wave stress loading and the hydrodynamic mechanism for earth tide stress loading and stress-dissipative heat mechanism for long period slow stress loading in the earthquake preparation stage. This paper illustrates the typical observation examples for each mode of stress loading and makes a preliminary study on their mechanisms.

关键词：反应机制井水温度应力加载模式载荷含水层系统水动力机制地震波

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有限域上完全对称多项式有很多零点

中国科学：数学 2021年第10期51卷 1677-1684页

作者：万大庆张俊 Department of Mathematics University of California at IrvineIrvineCA 92697USA 首都师范大学数学科学学院北京100048

有限域上多项式的零点计数问题是算术代数几何的核心问题之一.本文考虑有限域Fq上完全对称多项式的零点问题,主要结果如下:设h(x1,..., xk)∈Fq[x1,..., xk]是有限域Fq上一个m次完全对称多项式(k≥3, 1≤m≤q-3),(1)若m为奇数或者q为奇... 详细信息

有限域上多项式的零点计数问题是算术代数几何的核心问题之一.本文考虑有限域Fq上完全对称多项式的零点问题,主要结果如下:设h(x1,..., xk)∈Fq[x1,..., xk]是有限域Fq上一个m次完全对称多项式(k≥3, 1≤m≤q-3),(1)若m为奇数或者q为奇数,则多项式h(x1,..., xk)在Fqk中至少有6qk-3个零点;(2)若k≥4,则多项式h(x1,..., xk)在Fqk中至少有6(q-1)qk-4个零点.作为推论,我们证明了文献Zhang和wan (2020)中的猜想1.7.

关键词：完全对称多项式零点有限域

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Z_p-曲线塔的Zeta函数（英文）

四川师范大学学报（自然科学版） 2018年第4期41卷 427-438页

作者：万大庆加州大学欧文分校数学系美国欧文92674

本注记从Iwasawa理论思想出发,探讨了特征为Z_p-的有限域上几何曲线塔的Zeta函数的可能的稳定性质.并提出很多关于代数几何的Z_p-塔的问题和猜想.

关键词： Zp-塔代数几何 Zeta函数亏格斜率稳定亏格稳定

瞳孔大小对LASIK手术患者波前像差的影响

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中国实用眼科杂志 2006年第5期24卷 464-466页

作者：王大庆邓应平四川大学华西医院眼科成都610041

目的研究在标准LASIK手术前及术后1月波前像差与瞳孔大小的关系,认识LASIK术后出现眩光、暗视力下降、光晕等视觉质量下降的原因。方法采用WFA1000型主观像差仪得到37例(72眼)近视眼患者LASIK手术前和术后1月大瞳(>6.5mm)和小瞳(2-4mm)... 详细信息

目的研究在标准LASIK手术前及术后1月波前像差与瞳孔大小的关系,认识LASIK术后出现眩光、暗视力下降、光晕等视觉质量下降的原因。方法采用WFA1000型主观像差仪得到37例(72眼)近视眼患者LASIK手术前和术后1月大瞳(>6.5mm)和小瞳(2-4mm)的波前像差变化数据;然后用Matlab软件分析其结果,并做统计分析。结果像差与瞳孔大小密切相关,瞳孔越大,像差越大(p<0.01)。术后小瞳到大瞳的像差变化比术前更明显。在手术前,随瞳孔的增大,高阶像差中以彗差增加为主;手术后,随瞳孔的增大,球差的增加变得最显著。结论随着瞳孔的增大,无论在术前还是术后,都带来了更大的像差,而且术后像差的变化更大,这与病人夜间视力下降和眩光的临床表现相符。瞳孔大小在像差的形成中具有重要作用。

关键词：波前像差 LASIK 瞳孔近视

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BINGHAM液体在圆管中流动的稳定性

水动力学研究与进展（A辑） 1996年第2期11卷 119-126页

作者：吴文祥孙智康万利侯吉瑞胡靖邦大庆石油学院大庆采油一厂

将涡流模型［１］推广应用于研究一类带屈服应力的液体－Ｂｉｎｇｈａｍ液体在圆管中流动的稳定性，建立了判别其流动状态的判据──广义临界雷诺数Ｒｅｃ。同时将Ｍｉｓｈａ—Ｔｒｐａｔｈｉ［２］和ＨａｎＫｓ［３］流动稳定性理论用... 详细信息

将涡流模型［１］推广应用于研究一类带屈服应力的液体－Ｂｉｎｇｈａｍ液体在圆管中流动的稳定性，建立了判别其流动状态的判据──广义临界雷诺数Ｒｅｃ。同时将Ｍｉｓｈａ—Ｔｒｐａｔｈｉ［２］和ＨａｎＫｓ［３］流动稳定性理论用于该问题的研究。各模型的研究结果与Ｆｒｏｉｓｈｔｅｔｅｒ＆Ｖｉｎｏｇｒａｄｏｖ提供的实验数据［４］进行了比较。

关键词：涡流模型流动稳定性非牛顿液体流动状态

ON THE DIOPHANTINE EQUATION sum from i=1 to (?) x_i/d_i≡0(mod 1)AND ITS APPLICATIONS

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Chinese Annals of Mathematics 1986年第2期 232-236页

作者：孙琦万大庆马德刚 Department of Mathematics Sichuan University Chengdu China.

The number A（d1,…,dn）of solutions of the equation0（mod 1）,0 详细信息

The number A（d1,…,dn）of solutions of the equation0（mod 1）,0

关键词： mod 1)AND ITS APPLICATIONS x_i/d_i 一匀