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101.
A critical problem in large neural networks is over parameterization with a large number of weight parameters, which limits their use on edge devices due to prohibitive computational power and memory/storage requirements. To make neural networks more practical on edge devices and real-time industrial applications, they need to be compressed in advance. Since edge devices cannot train or access trained networks when internet resources are scarce, the preloading of smaller networks is essential. Various works in the literature have shown that the redundant branches can be pruned strategically in a fully connected network without sacrificing the performance significantly. However, majority of these methodologies need high computational resources to integrate weight training via the back-propagation algorithm during the process of network compression. In this work, we draw attention to the optimization of the network structure for preserving performance despite compression by pruning aggressively. The structure optimization is performed using the simulated annealing algorithm only, without utilizing back-propagation for branch weight training. Being a heuristic-based, non-convex optimization method, simulated annealing provides a globally near-optimal solution to this NP-hard problem for a given percentage of branch pruning. Our simulation results have shown that simulated annealing can significantly reduce the complexity of a fully connected network while maintaining the performance without the help of back-propagation. 相似文献
102.
Po King Ng Xiong Gong Wing Tak Wong Wai Kin Chan 《Macromolecular rapid communications》1997,18(12):1009-1016
A series of novel quinoxaline-based conjugated polymers which contain a ruthenium(II) bipyridine complex were synthesized by the Suzuki coupling reactions. UV/VIS spectroscopy showed that the spectral features of the polymers are dependent on the amount of metal complex present. Results from excitation and emission spectroscopy suggest an energy transfer between the backbone and the metal complex. The polymers exhibit hole carrier mobilities of ≈ 10−5 cm2 · V−1 · s−1, which is comparable to organic photoconductors. 相似文献
103.
104.
Kwong FY Li YM Lam WH Qiu L Lee HW Yeung CH Chan KS Chan AS 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(13):3872-3880
An interesting rhodium-catalyzed asymmetric aqueous Pauson-Khand-type reaction was developed. A chiral atropisomeric dipyridyldiphosphane ligand was found to be highly effective in this system. This operationally simple protocol allows both catalyst and reactants to be handled under air without precautions. Various enynes were transformed to the corresponding bicyclic cyclopentenones in good yield and enantiomeric excess (up to 95 % ee). A study of the electronic effects of the enyne substrates revealed a correlation between the electronic properties of the substrates and the ee value obtained in the product of the Pauson-Khand-type reaction. A linear free-energy relationship was observed from a Hammett study. 相似文献
105.
We analyze a holey fiber that consists of a circular distribution of air holes by the radial effective-index method. By this method, we show that the holey fiber is a leaky structure and its extended single-mode operation is governed by the differential leakage loss between the first two modes of the fiber. The effects of the hole size and the hole separation on the leakage losses of the first two modes are calculated. The leakage loss of the fundamental mode of the fiber is found to be comparable to that of a conventional holey fiber that has a hexagonal distribution of air holes. 相似文献
106.
Gordon E. Langford Peter Yates Hin Wing Yeung Kin Fai Cheng 《Magnetic resonance in chemistry : MRC》1980,14(6):474-478
The 13C NMR spectra of leonurine hydrochloride and thirteen of its analogues in DMSO-d6 have been analyzed. Changes in the aromatic substituents have no significant effect on the chemical shifts of the side chain methylene carbons indicating that they do not influence the conformation of the latter. Observed deviations from additivity of substituent effects for the methylene carbon chemical shifts suggest that the methylene side chains of these compounds may be more tightly coiled than are the corresponding n-alkanes. In representative cases no change in conformation is evident in 50% aqueous DMSO-d6 solutions, indicating that similar considerations may apply in aqueous media. 相似文献
107.
Kin Chung Lo 《Mathematical Social Sciences》2011,62(2):109-113
We formulate the permissibility concept (Brandenburger, 1992) in terms of general preference, and prove that the solution concept characterizes rationality, caution, and common “belief” of rationality and caution. 相似文献
108.
Ho Doris M. L. Nelwamondo Aubrey N. Okubo Ayako Ramebäck Henrik Song Kyuseok Han Sun Ho Hancke Jacobus J. Holmgren Stina Jonsson Sofia Kataoka Osamu Lagerkvist Petra Lee Chi-Gyu Lim Sang Ho Park Jinkyu Park Jong-Ho Pong Boon Kin Sandström Björn Shinohara Nobuo Tan Angela H. J. Toda Nobufumi Tovedal Annika Vesterlund Anna 《Journal of Radioanalytical and Nuclear Chemistry》2018,315(2):353-363
Journal of Radioanalytical and Nuclear Chemistry - The Fourth Collaborative Material Exercise (CMX-4) of the Nuclear Forensics International Technical Working Group (ITWG) registered the largest... 相似文献
109.
Ab initio path‐integral calculations of kinetic and equilibrium isotope effects on base‐catalyzed RNA transphosphorylation models 下载免费PDF全文
Detailed understandings of the reaction mechanisms of RNA catalysis in various environments can have profound importance for many applications, ranging from the design of new biotechnologies to the unraveling of the evolutionary origin of life. An integral step in the nucleolytic RNA catalysis is self‐cleavage of RNA strands by 2′‐O‐transphosphorylation. Key to elucidating a reaction mechanism is determining the molecular structure and bonding characteristics of transition state. A direct and powerful probe of transition state is measuring isotope effects on biochemical reactions, particularly if we can reproduce isotope effect values from quantum calculations. This article significantly extends the scope of our previous joint experimental and theoretical work in examining isotope effects on enzymatic and nonenzymatic 2′‐O‐transphosphorylation reaction models that mimic reactions catalyzed by RNA enzymes (ribozymes), and protein enzymes such as ribonuclease A (RNase A). Native reactions are studied, as well as reactions with thio substitutions representing chemical modifications often used in experiments to probe mechanism. Here, we report and compare results from eight levels of electronic‐structure calculations for constructing the potential energy surfaces in kinetic and equilibrium isotope effects (KIE and EIE) computations, including a “gold‐standard” coupled‐cluster level of theory [CCSD(T)]. In addition to the widely used Bigeleisen equation for estimating KIE and EIE values, internuclear anharmonicity and quantum tunneling effects were also computed using our recently developed ab initio path‐integral method, that is, automated integration‐free path‐integral method. The results of this work establish an important set of benchmarks that serve to guide calculations of KIE and EIE for RNA catalysis. © 2014 Wiley Periodicals, Inc. 相似文献
110.
Xin Wang Zi-Qi Li Binh Khanh Mai John A. Gurak Jr Jessica E. Xu Van T. Tran Hui-Qi Ni Zhen Liu Zhonglin Liu Kin S. Yang Rong Xiang Peng Liu Keary M. Engle 《Chemical science》2020,11(41):11307
We report a series of palladium(ii)-catalyzed, intramolecular alkene hydrofunctionalization reactions with carbon, nitrogen, and oxygen nucleophiles to form five- and six-membered carbo- and heterocycles. In these reactions, the presence of a proximal bidentate directing group controls the cyclization pathway, dictating the ring size that is generated, even in cases that are disfavored based on Baldwin''s rules and in cases where there is an inherent preference for an alternative pathway. DFT studies shed light on the origins of pathway selectivity in these processes.We report a series of palladium(ii)-catalyzed, intramolecular alkene hydrofunctionalization reactions with carbon, nitrogen, and oxygen nucleophiles to form five- and six-membered carbo- and heterocycles. 相似文献