上跨软土深基坑的钢格构柱连续刚构铁路便桥振动性能分析

为满足某上跨软土深基坑的钢格构柱现浇钢筋混凝土梁板连续刚构干线铁路便桥竖、横向刚度评估的需要,计算了软土深基坑挖土过程中便桥结构的桥体动力特性.采用随机振动理论,仿真分析了客货列车通过便桥时的运营性能及结构振动响应,结果表明,在统计意义上与实测结果基本吻合.深入探讨了多方案便桥结构的振动性能.研究结果表明,即使在软土深基坑开挖期间,该便桥结构也能确保列车限速安全、平稳运营.提出了便桥结构体系的局部优化建议.     

RELATIONS OF DERIVATIVE ALGEBRA AND RING OF DIFFERENTIAL OPERATORS IN CHARACTERISTIC p>0

Introduction　　 Let K be a field,K [X ]∶=K [x1,… ,xn]bethe polynomial ring in n variables.We know thatwhen K is a field with ch( K ) =0 ,then the Weylalgebra An( K) ,the ring of differential operatorsD( K[X]) ,and the derivative algebraΔ ( K [X])which is generated by{xi, i| i=1 ,… ,n}in End KK[X]are all isomorphic[1～ 3 ] .But if ch( K) =p>0 ,the three do not have that relation.In factΔ( K[X]) is only a quotientof An( K) [4] ;and Ref.[5 ]gives a comprehensive study to the rela…     

Several Norms of Operators on Banach Lattices

We present some positive results involving the several norms of operators on Banach lattices, which shows several relations of these operator norms.     

NEW WIND-INDUCED RESPONSES ANALYSIS METHOD OF SPATIAL STRUCTURES IN FREQUENCY DOMAIN WITH MODE COMPENSATION

IntroductionIn response to the demand for architecture anduse function,the span of stadiums or gymnasiumsis enlarging,which inevitably tends to involvelight- weigh roofs,such as membrane.Thesestructures with long natural periods is sensitive towind vibrations,therefore the effects of windloads,especially of dynamic wind loads,are be-coming significant at their design stage.It isknown that these types of structures are apt tohave many natural frequencies in a narrow frequen-cy range.This fact d…     

基于有限格蕴涵代数的格值命题逻辑语义系统

以有限格蕴涵代数作为逻辑系统的真值域，在其上建立了基于有限格蕴涵代数的格值命题逻辑语义系统，研究了在A水平上系统的赋值和公式的可满足性等基本定义，证明了系统“有效性”的可判定性并给出了判定算法。     

三维机翼尾涡面卷曲的数值模拟

采用离散涡环法来模拟三维机翼的升力效应，机翼尾涡面由双曲四边形面元进行离散．每个面元上布置线性偶极子分布，由尾涡面上的运动学条件来确定三维涡面卷曲形状，在诱导速度计算中引入了非奇异化的光滑参数，数值模拟结果显示了本方法的有效性，与试验结果和其他数值方法相比是吻合的．     

排桩支护结构内支撑优化设计

针对石家庄地区的地质水文情况,对于排桩内支撑基坑支护体系,于基坑中部增加一道格构柱作为钢支撑支点的设计方案,相比无格构柱的钢支撑设计方案,可以起到减少深基坑钢支撑道数、避免出现倒换支撑、节约投资、便于施工等作用。为详细说明排桩钢支撑支护体系增加格构柱支点设计方案的优势,通过结合石家庄地铁3号线一期工程小灰楼站的设计方案,采用深基坑设计软件FRWS7.1进行支护体系验算和技术、经济比对分析,从而验证了该方案的可行性和经济性。     

基于泛布尔代数的交通信号控制的数据挖掘

提出了将基于泛布尔代数理论的数据挖掘技术应用到城市交通信号控制中。针对城市单个T形交叉路口的交通流控制,利用这种新的数据挖掘技术对其进行了初步分析,采用了多相位实时控制策略;对提取的决策规则,建立起决策系统的泛布尔模型。仿真结果表明,通过这种新的数据挖掘技术得出的控制模型,对实时改善交通流的管理和控制,效果优于传统的交通流控制技术。     

FILTERED-GRADED TRANSFER OF SAGBI BASES IN SOLVABLE POLYNOMIAL ALGEBRAS

IntroductionThe method of SAGBI bases calculations in-troduced by Refs.[1 ,2 ]has turned out to be apowerful tool in the subalgebra theory of solvablepolynomial algebras(including commutative poly-nomial algebras,iterated Ore extensions,universalenveloping algebras of finite dimensional Lie alge-bras and particulary Weyl algebras) [3 ] .The aboveSAGBI bases give well hehaved generating sets ofsubalgebras.In this paper,by mimicking Li andWu' s method of filtered- graded transfer of Groeb…     

Numerical analysis of acoustic band gaps in two-dimensional periodic materials

Using the plane-wave expansion （PWE） method , the band gaps of the two-dimension phononic crystals composed of square, triangle and honeycomb arrays aluminum cylinders in the air are calculated numerically. The band structures of three lattices were compared and analyzed. It is concluded that the band-gap of honeycomb lattices is located at lower frequency fields, compared with square and triangle lattices, When the filling fraction is between 0. 091 and 0. 604 6, the honeycomb lattices have larger band gaps and gain an advantage over square and triangle lattices. In addition, the gap map is introduced to illustrate the influences of filling fraction on the number, the relative width and the limit frequency of the band-gap.