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How annealing influences the morphology of a highly regioregular poly(3‐hexylthiophene) (RR‐P3HT) film at the substrate interface as well as the lateral inhomogeneity in the electronic structure of the film are elucidated. Whereas previous studies have reported that high‐molecular‐weight (MW) RR‐P3HT films tend to show low crystallinity even after annealing, it is found that high‐MW RR‐P3HT does show high crystallinity after annealing at high temperature for a long time. Photoemission electron microscopy (PEEM), X‐ray photoemission spectroscopy, and ultraviolet photoemission spectroscopy results clearly resolve a considerable lateral inhomogeneity in the morphology of RR‐P3HT film, which results in a variation of the electronic structure depending on the local crystallinity. The PEEM results show how annealing facilitates crystal growth in a high‐MW RR‐P3HT film.  相似文献   
3.
Likelihood and the Bayes procedure   总被引:2,自引:0,他引:2  
Hirotugu Akaike 《TEST》1980,31(1):143-166
Summary In this paper the likelihood function is considered to be the primary source of the objectivity of a Bayesian method. The necessity of using the expected behavior of the likelihood function for the choice of the prior distribution is emphasized. Numerical examples, including seasonal adjustment of time series, are given to illustrate the practical utility of the common-sense approach to Bayesian statistics proposed in this paper.  相似文献   
4.
H. Nakamura  H. Akaike 《Automatica》1981,17(1):143-155
The use of a multivariate autoregressive model for the implementation of a new practical optimal control of a supercritical thermal power plant is discussed. The control is realized by identifying the system characteristics of the plant under the conventional PID control by the autoregressive model fitting and then implementing the digital control to correct the defect of the analog control. The procedure of identification and the controller implementation is described in detail by using the experimental results of a real plant. The results clearly demonstrate the advantage of the new controller over the conventional PID controller. The experience of the commercial operation of the plant confirms that the new controller is extremely robust against the gradual change of the plant characteristics, and this shows the practical utility of the identification procedure on which the design of the controller is based.  相似文献   
5.
Stochastic theory of minimal realization   总被引:2,自引:0,他引:2  
In this paper it is shown that a natural representation of a state space is given by the predictor space, the linear space spanned by the predictors when the system is driven by a Gaussian white noise input with unit covariance matrix. A minimal realization corresponds to a selection of a basis of this predictor space. Based on this interpretation, a unifying view of hitherto proposed algorithmically defined minimal realizations is developed. A natural minimal partial realization is also obtained with the aid of this interpretation.  相似文献   
6.
A new look at the statistical model identification   总被引:177,自引:0,他引:177  
The history of the development of statistical hypothesis testing in time series analysis is reviewed briefly and it is pointed out that the hypothesis testing procedure is not adequately defined as the procedure for statistical model identification. The classical maximum likelihood estimation procedure is reviewed and a new estimate minimum information theoretical criterion (AIC) estimate (MAICE) which is designed for the purpose of statistical identification is introduced. When there are several competing models the MAICE is defined by the model and the maximum likelihood estimates of the parameters which give the minimum of AIC defined by AIC = (-2)log-(maximum likelihood) + 2(number of independently adjusted parameters within the model). MAICE provides a versatile procedure for statistical model identification which is free from the ambiguities inherent in the application of conventional hypothesis testing procedure. The practical utility of MAICE in time series analysis is demonstrated with some numerical examples.  相似文献   
7.
The electrogenic Na/K pump current (Ip) was studied in the dissociated neostriatal neurons of the rat by using the nystatin-perforated patch recording mode. The Ip was activated by external K+ in a concentration-dependent manner with an EC50 of 0.7 mM at a holding potential (VH) of -40 mV. Other monovalent cations also caused Ip and the order of potency was Tl+>K+, Rb+>NH4+, Cs+>Li+. The Ip decreased with membrane hyperpolarization in an external solution containing 150 mM Na+, while the Ip did not show such voltage dependency without external Na+. Ouabain showed a steady-state inhibition of Ip in a concentration- and temperature-dependent manner at a VH of -40 mV. The IC50 values at 20 and 30 degrees C were 7.1 x 10(-6) and 1.3 x 10(-6) M, respectively. The decay of Ip after adding ouabain well fitted with a single exponential function. At a VH of -40 Mv, the association (k+1) and dissociation (k-1) rate constants estimated from the time constant of the current decay at 20 degrees C were 4.0 x10(2) s-1 M-1 and 6.3 x 10(-3) s-1, respectively. At 30 degrees C, k+1 increased to 2.8 x 10(3) s-1 M-1 while k-1 showed no such change with a value of 1.8 x 10(-3) s-1. A continuous Na+ influx was demonstrated by both the Na+-dependent leakage current and tetrodotoxin-sensitive Na+ current, which resulted in the continuous activation of the Na/K pump. It was thus concluded that the Na/K pump activity was well-maintained in the dissociated rat neostriatal neurons with distinct functional properties and that the activity of the pump was tightly connected with Na+ influxes.  相似文献   
8.
Insects are known to be useful in estimating the postmortem interval (PMI). Here several cases are reported which show that a wide range of applications in medicolegal questions and hygiene together or apart from estimating the PMI can be answered by use of forensic entomology techniques, including close observation of larval development. Case 1 describes how blowfly larvae fell from a putrefied corpse, hid, and finally emerged from pupae three months after disinfection and renovation. In case 2, the entomological state of the decomposed corpse of a heroin user is described. Case 3 deals with a single adult Protophormia terranovae found in the skull of a partially mummified woman. Case 4 reports the finding of Serratia marcescens bacteria in red Muscina stabulans pupae which were found on a 5-day-old corpse. In case 5, blowfly eggs on the corpse of another heroin user are interpreted as an indication of the decedent being laid outside at night after his death in a flat. Case 6 deals with the finding of Parasarcophaga argyrostoma, which in Cologne might be an indicator species which tells if a corpse was lying outside at least for some time.  相似文献   
9.
Voltage-dependent Ca2+ channels play a central role in controlling neurotransmitter release at the synapse. They can be inhibited by certain G-protein-coupled receptors, acting by a pathway delimited to the membrane. In addition, modulation of Ca2+ channel activity by protein kinases also contributes to the dynamic regulation of neuronal physiology. Recently, differences in these modulations between Ca2+ channel subtypes have been shown in several neuronal preparations. Here we show that two types of presynaptic Ca2+ channel (N-type and Q-type) are differentially regulated by cAMP and G-proteins using a Xenopus oocyte expression system. Treatment to increase cytosolic cAMP concentration with forskolin and 3-isobutyl-1-methylxanthine (IBMX) markedly potentiated Q-type channel current, and the enhancement was reversed by protein kinase A inhibitors. Much smaller enhancement was observed in N-type channel current after the cAMP elevation. When large depolarizing prepulse was applied to the oocytes for evaluation of the tonic inhibition of Ca2+ channels by intrinsic G-protein activity, N-type channel current elicited a large prepulse facilitation but Q-type channels did not. The tonic inhibition of N-type channels was abolished by an intracellular perfusion with a 'cut-open' recording configuration, or by co-expression with G(alpha o). When kappa opioid receptors were co-expressed and stimulated with agonists, depolarization-resistant inhibition was more apparent in Q-type channels than in N-type channels. These results suggest that Q-type channels are more susceptible to the protein kinase A-mediated facilitation than N-type channels, and that activity of N-type channels can be more highly regulated in a voltage-dependent manner by G(betagamma) than that of Q-type channels. These differences may account for the selective regulation of neurotransmitter release by these Ca2+ channels.  相似文献   
10.
A protocol control system architecture that provides very high processing performance for gigabit-per-second data communication in a broadband network is described. The architecture connects protocol controllers in parallel and uses a distributed multilink method that features a distributed algorithm for allocating transmission on the transmitting side and a resequencing algorithm on the receiving side. The system performance and the influence of transmission errors caused by cell loss in an asynchronous transfer mode network are evaluated. It is shown that by reducing each controller's distributing overhead, the system increases throughput up to 90 times that achieved when using a single controller  相似文献   
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