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51.
Let * be a star operation on an integral domain D. Let f (D) be the set of all nonzero finitely generated fractional ideals of D. Call D a *-Prüfer (respectively, (*, v)-Prüfer) domain if (FF ?1)* = D (respectively, (F v F ?1)* = D) for all F ∈  f (D). We establish that *-Prüfer domains (and (*, v)-Prüfer domains) for various star operations * span a major portion of the known generalizations of Prüfer domains inside the class of v-domains. We also use Theorem 6.6 of the Larsen and McCarthy book [30 Larsen , M. D. , McCarthy , P. J. ( 1971 ). Multiplicative Theory of Ideals . New York : Academic Press . [Google Scholar]], which gives several equivalent conditions for an integral domain to be a Prüfer domain, as a model, and we show which statements of that theorem on Prüfer domains can be generalized in a natural way and proved for *-Prüfer domains, and which cannot be. We also show that in a *-Prüfer domain, each pair of *-invertible *-ideals admits a GCD in the set of *-invertible *-ideals, obtaining a remarkable generalization of a property holding for the “classical” class of Prüfer v-multiplication domains. We also link D being *-Prüfer (or (*, v)-Prüfer) with the group Inv*(D) of *-invertible *-ideals (under *-multiplication) being lattice-ordered.  相似文献   
52.
In the last few years, the concepts of stability and Clifford regularity have been fruitfully extended by using star operations. In this article we deepen the study of star stable and star regular domains and relate these two classes of domains to each other.  相似文献   
53.
激光器件的优良性能大大提升了它在武器系统中的应用前景。上位模拟器是模拟武器系统对激光点火系统实施指令的控制单元,通过上位模拟器的操作可以实现对激光点火系统的远程控制。上位模拟器的研究是基于硬件和控制软件的,具备有发火控制、保险与解除保险控制、通讯、温度检测与背向光检测等多种控制功能。上位模拟器的研究为激光点火系统在武器系统中的实际应用奠定了良好的基础。  相似文献   
54.
55.
The star products in symbolic dynamics, as effective algebraic operations for describing self-similar bifurcation structure in classical dynamical systems, are found to have either associativity or non-associativity. In this Letter, non-associative star products in trimodal iterative dynamical systems are considered. As the left and right operations have different effects, right-associative star products break the conventional Feigenbaum's metric universality. Through high precision parallel computation, it is found that period-p-tupling bifurcation processes described by right-associative star products exhibit a superconvergent universality of double exponential form.  相似文献   
56.
Core-shell type multiarm star copolymers with poly(ε-caprolactone) (PCL) as shells and hyperbranched polyethylenimine (PEI) as core have been successfully prepared by the Sn(Oct)2 catalyzed ring-opening polymerization of ε-caprolactone (CL) using high molecular weigh PEIs directly as macroinitiators. The initiation efficiency is in the range of 91-95% for PEI with Mn = 104 (PEI10K) and only around 60% for PEI with Mn = 2.5 × 104 (PEI25K), leading to star polymers with an average arm number in the range of 155-276. The thermal property of the obtained multiarm star polymers were also investigated by DSC. The melting and crystallization temperatures of the star polymers increase as the PCL arm length increases when the PEI core is fixed. The fusion enthalpy, crystalline enthalpy and degree of crystallinity values of the star polymers with PEI10K core are less than those with PEI1.8K core. Due to the polarity difference between PCL arm and PEI core, the resulting multiarm star polymers can act as inverted micellar nanocapsules capable of extracting and encapsulating water soluble guests. Increasing the size and polarity of the hydrophilic PEI core of the star nanocapsules are two effective ways to enhance their hydrophilic guest encapsulation capacity. Increasing the hydrophobic PCL arm length can increase the molar ratio, whereas reduce the weight ratio of the encapsulated hydrophilic guests to the star nanocapsules. Unexpectedly, the obtained nanocapsules can entrap the bigger size hydrophilic congo red guests more than the smaller size methyl orange.  相似文献   
57.
对星模光学系统中各种像差对几何中心位置的影响及像差对显示星点能量中心位置造成的偏差进行了分析与综合评估.分析结果表明,视场位置越大的星点产生的像点能量越不均匀,重心偏移越明显,系统中慧差和畸变对于星点能量中心影响较大.根据球面镜组成的共轴光学系统性质可知,能量中心的偏移发生在星点所在极半径方向上,因此提出了一种基于极坐标的星点位置修正方法,只需在星点所在方向对极半径进行修正.该方法简化了基于二维坐标轴分区修正的过程,减少了数据计算量.利用极坐标修正方法对星模拟器修正前后的单星位置误差进行了测试,实验结果表明极坐标修正过程较以往修正方法简单快捷,且修正结果更加准确.  相似文献   
58.
针对目前便携式防空导弹模拟训练设备成本高,精度低的缺点,提出了基于激光测距原理的便携式防空导弹模拟训练系统。系统由模拟训练弹和三维投影系统构成,利用安装在模拟训练弹上的激光距离传感器、倾角传感器作为敏感元件判断射手瞄准点坐标,采用实时三维仿真软件生成目标并通过投影仪投影作为射手瞄准的目标。阐述了系统的结构、工作原理,捕获目标判断过程、校准过程并分析了系统的误差,应用表明系统具有成本较低,安装调试方便,判断精度高的特点。系统将激光测距系统和角度传感器配合使用,较大的降低了对角度传感器的精度要求,由此带来设备成本的大幅度降低和可靠性的增加。  相似文献   
59.
Jiaqun Wei   《Journal of Algebra》2007,310(2):903-916
We give conditions under which an n-star module extends to an n-star module, or an n-tilting module, over a ring extension R of A. In case that R is a split extension of A by Q, we obtain that is a 1-tilting module (respectively, a 1-star module) if and only if is a 1-tilting module (respectively, a 1-star module) and generates both and (respectively, generates ), where is an injective cogenerator in the category of all left A-modules. These extend results in [I. Assem, N. Marmaridis, Tilting modules over split-by-nilpotent extensions, Comm. Algebra 26 (1998) 1547–1555; K.R. Fuller, *-Modules over ring extensions, Comm. Algebra 25 (1997) 2839–2860] by removing the restrictions on R and Q.  相似文献   
60.
In this paper, we establish an extension of Funk's section theorem. Our result has the following corollary: If is a star body in whose central -slices have the same volume (with appropriate dimension) as the central -slices of a centered body , then the dual quermassintegrals satisfy , for any , with equality if and only if . The case that is a centered body implies Funk's section theorem.

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