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41.
S.C. Lim 《Physics letters. A》1980,79(1):13-15
An attempt to extend Nelson's stochastic quantization procedure to tensor fields indicates that the results of Guerra et al. on the connection between a euclidean Markov scalar field and a stochastic scalar field fails to hold for tensor fields. 相似文献
42.
The bbody, 4-body and 5-body quantum mechanical systems with pairwise interactions having repulsive core and attractive tail and with completely symmetric permutation symmetry in the spatial wavefunctions are studied. The spatial distribution of the wavefunctions of the low-lying O+ states is investigated in detail. The features of the geometric structures and of the internal motions of each of these states are revealed. Certain modes of the internal motions are discovered. 相似文献
43.
Hong Oh Kim Rae Young Kim Jae Kun Lim Zuowei Shen 《Journal of Approximation Theory》2007,147(2):196-204
We start with a characterization of a pair of frames to be orthogonal in a shift-invariant space and then give a simple construction of a pair of orthogonal shift-invariant frames. This is applied to obtain a construction of a pair of Gabor orthogonal frames as an example. This is also developed further to obtain constructions of a pair of orthogonal wavelet frames. 相似文献
44.
In this article, we investigate some conditions for a real cyclic extension K over Q to satisfy the property that every totally positive unit of K is a square. As an application, we give a partial answer to Taussky's conjecture. We then extend our result to real abelian extensions of certain type. 相似文献
45.
With the increasing emphasis on supply chain vulnerabilities, effective mathematical tools for analyzing and understanding appropriate supply chain risk management are now attracting much attention. This paper presents a stochastic model of the multi-stage global supply chain network problem, incorporating a set of related risks, namely, supply, demand, exchange, and disruption. We provide a new solution methodology using the Moreau–Yosida regularization, and design an algorithm for treating the multi-stage global supply chain network problem with profit maximization and risk minimization objectives. 相似文献
46.
Ae Ran Lim 《Applied magnetic resonance》2014,45(1):9-17
To clarify the nature of microscopic structural changes of N(CH3)4CdCl3 at high temperatures, the nuclear magnetic resonance (NMR) spectra of the protons and carbons in N(CH3)4CdCl3 were measured. NMR studies of the 1H and 13C spin–lattice relaxation time, T 1ρ, in the rotating frame were also performed. No changes in the T 1ρ of 1H and 13C associated with the N(CH3)4 groups were observed at the high-temperature transition from phase I to phase I′. However, the 14N NMR spectra reflected changes in the structural geometry during the transition to phase I′, indicating that this transition is driven by N(CH3)4. 相似文献
47.
K. Venkatakrishnan B.K.A. Ngoi P. Stanley L.E.N. Lim B. Tan N.R. Sivakumar 《Applied Physics A: Materials Science & Processing》2002,75(4):493-496
Photomasks are the backbone of microfabrication industries. Currently they are fabricated by a lithographic process, which
is very expensive and time consuming since it is a multi-step process. These issues can be addressed by fabricating photomasks
by direct femtosecond laser writing, which is a single-step process and comparatively cheaper and faster than lithography.
In this paper we discuss our investigations on the effect of two types of laser writing techniques, namely front- and rear-side
laser writing, with regard to the feature size and the edge quality of a feature. It is proved conclusively that for the patterning
of masks, front-side laser writing is a better technique than rear-side laser writing with regard to smaller feature size
and better edge quality. Moreover the energy required for front-side laser writing is considerably lower than that for rear-side
laser writing.
Received: 22 May 2001 / Accepted: 14 September 2001 / Published online: 17 October 2001 相似文献
48.
In this paper, we study a problem central to crossdocking that aims to eliminate or minimize storage and order picking activity using JIT scheduling. The problem is modelled naturally as a machine scheduling problem. As the problem is NP-hard, and for real-time applications, we designed and implemented two heuristics. The first uses Squeaky Wheel Optimization embedded in a Genetic Algorithm and the second uses Linear Programming within a Genetic Algorithm. Both heuristics offer good solutions in experiments where comparisons are made with the CPLEX solver. 相似文献
49.
Let 𝔽 be a field of characteristic two. Let S n (𝔽) denote the vector space of all n?×?n symmetric matrices over 𝔽. We characterize i. subspaces of S n (𝔽) all whose elements have rank at most two where n???3, ii. linear maps from S m (𝔽) to S n (𝔽) that sends matrices of rank at most two into matrices of rank at most two where m, n???3 and |𝔽|?≠?2. 相似文献
50.
The interfacial electronic structures of molybdenum oxide (MoOx) deposited on fullerene (C60) which could be used as a hole-injecting layer in inverted top-emitting organic light-emitting diodes (TE-OLEDs) were investigated by photoemission spectroscopy. The hole-injecting barrier height (ΦBh) at each interface investigated by an ultraviolet photoemission spectroscopy was reduced to from 1.4 to 0.1 eV as the thickness of MoOx (ΘMoOx) was increased from 0.1 to 5.0 nm on C60. In these interface system, the sign of vacuum-level shift, highest occupied molecular orbital (HOMO)-level shift, and core-level shifts were all positive indicating that the interface mechanism is attributed to the work-function differences due to a band bending at these interfaces. Moreover, the near-edge X-ray absorption fine structure spectra at carbon K-edge did not show any structural modification as well as any chemical reaction at the MoOx-on-C60 interfaces when ΘMoOx was changed on C60. From these results, the inverted TE-OLED with C60 (5.0 nm)/MoOx (5.0 nm) showed the power efficiency of 1.7 lm/W at a luminance of about 1000 cd/m2 and the maximum luminance of about 76.000 cd/m2 at the bias voltage of 11.0 V. It exhibited the highest performance among the inverted TE-OLEDs fabricated as a function of MoOx thickness from 0 to 5.0 nm. 相似文献