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991.
Kwok Wai Lau 《代数通讯》2013,41(7):2617-2629
The generators of the Temperley-Lieb algebra generate a monoid with an appealing geometric representation. It has been much studied, notably by Louis Kauffman. Borisavljevi?, Do?en, and Petri? gave a complete proof of its abstract presentation by generators and relations, and suggested the name “Kauffman monoid”. We bring the theory of semigroups to the study of a certain finite homomorphic image of the Kauffman monoid. We show the homomorphic image (the Jones monoid) to be a combinatorial and regular *-semigroup with linearly ordered ideals. The Kauffman monoid is explicitly described in terms of the Jones monoid and a purely combinatorial numerical function. We use this to describe the ideal structure of the Kauffman monoid and two other of its homomorphic images. 相似文献
992.
K.K. Yee 《Molecular physics》2013,111(2):513-525
The utility of the [1, 0] Padé approximant in the determination of long-range interaction constants is investigated using the recently calculated Rydberg-Klein-Rees potentials for the B3ΠOu + states of I2, Br2 and Cl2. The conditions under which the [1, 0] Padé approximant is a valid representation of the long-range potential outside the electron-overlap region are studied in detail, using as model systems the B states of I2, Br2 and Cl2, and the X1Σg+, B1Σu+ and B′1Σu+ states of H2. In general, the validity of the representation depends on the nature of the potential, and is governed by if the long-range potential can be adequately represented by a maximum number of three terms (n, m, m1) in the inverse-power expansion. 相似文献
993.
We designed and fabricated gallium nitride (GaN) subwavelength grating (SWG) structures on GaN/sapphire via patterning using the periodic silica sphere monolayer array as an etch mask and a subsequent dry etching for efficient antireflection coatings. Theoretical optimization of GaN SWG structures was performed in terms of their geometrical parameters by the rigorous coupled-wave analysis simulation using a theoretical structural model. The bullet-like parabola-shaped SWGs with a large height-to-diameter ratio (R H/D) yielded good broadband and wide-angle antireflective surface properties. Considering the R H/D, the GaN SWG structure using 320-nm silica spheres theoretically and experimentally exhibited the most efficient antireflection property because it provided a linearly graded effective refractive index profile with relatively long relaxation length. For various geometries of the fabricated GaN SWGs on GaN/sapphire, the calculated reflectance results showed a similar tendency with the experimental results. 相似文献
994.
Adrian E. Raftery Xiaoyue Niu Peter D. Hoff Ka Yee Yeung 《Journal of computational and graphical statistics》2013,22(4):901-919
Multilevel modeling is a popular statistical technique for analyzing data in hierarchical format, and thus naturally fits within a distributed database framework. We consider the computational aspects of multilevel modeling across distributed databases. In addition, we consider these aspects under a generalization of the multilevel model where the distributed groups (or databases) are allowed to specify different models at both level-1 (individual) and level-2 (group). For a variety of scenarios, we develop the distributed computation algorithm for two-step least squares (LS) estimators and also for iterative MLE estimators of the parameters of interest; in particular, we determine the required data structure at each computing site, the necessary information (original data, cross-product matrices, coefficient vectors), and the order in which such information needs to be passed between sites. Finally, we discuss recursive updating, fault tolerance, and security issues. 相似文献
995.
We give a new generalization of the spt-function of G.E. Andrews, namely $\operatorname {Spt}_{j}(n)$ , and give its combinatorial interpretation in terms of successive lower-Durfee squares. We then generalize the higher order spt-function $\operatorname {spt}_{k}(n)$ , due to F.G. Garvan, to ${}_{j\!}\operatorname {spt}_{k}(n)$ , thus providing a two-fold generalization of $\operatorname {spt}(n)$ , and give its combinatorial interpretation. Lastly, we show how the positivity of j spt k (n) can be used to generalize Garvan’s inequality between rank and crank moments to the moments of j-rank and (j+1)-rank. 相似文献
996.
Hyung Won Lee Kyoung Yee Kim Yun Soo Myung 《The European Physical Journal C - Particles and Fields》2011,71(3):1585
We investigate the Brans–Dicke (BD) theory with the potential as cosmological model to explain the present accelerating universe.
In this work, we consider the BD field as a perfect fluid with the energy density and pressure in the Jordan frame. Introducing
the power-law potential and the interaction with the cold dark matter, we obtain the phantom divide which is confirmed by
the native and effective equation of state. Also we can describe the metric f(R) gravity with an appropriate potential, which shows a future crossing of the phantom divide in viable f(R) gravity models when employing the native and effective equations of state. 相似文献
997.
998.
Antony Wing Hung Ng Chi‐Chung Yee Ho Yu Au‐Yeung 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(48):17536-17543
A pair of radial [5]catenanes, with either an isomeric cyclic ‐AABB‐ or ‐ABAB‐ type sequence of the interlocked β‐cyclodextrin (β‐CD) and cucurbit[6]uril (CB[6]) units, has been efficiently synthesized. Because of a marked difference in the binding strength and interlocking sequence of the peripheral macrocycles, interesting sequence‐dependent properties, characteristic of mechanically bonded macrocycles, were realized. Variable‐temperature 1H NMR studies showed that the ‐ABAB‐ isomer has a more independent β‐CD dynamic, whereas the β‐CD motions in the ‐AABB‐ isomer are coupled. Dynamics of the pH‐insensitive β‐CD can also be further modulated upon base‐triggered mobilization of the CB[6]. These unique properties of the mechanical bond expressed in a sequence‐specific fashion and the transmission of the control on the macrocycle dynamics from one interlocked component to another, highlight the potential of similar complex hetero[n]catenanes in the design of advanced, multicomponent molecular machines. 相似文献
999.
We show that there are exactly five different classes of complete regularity determined by finite topological spaces. 相似文献
1000.