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1.
对中外商业方法专利保护的制度与实践进行了积极探索和研究。介绍了商业方法及商业方法专利概念的不同规定,并提出了自己的看法和见解;分析美日欧商业方法专利的保护状况、特点和贡献,对我国商业方法专利保护的现状及存在的问题进行了剖析;最后,对我国在商业方法专利保护方面所面临的挑战提出了笔者的应对策略。  相似文献   

2.
The bootstrap, like the jack-knife, is a technique for estimating standard errors. The idea is to use Monte Carlo simulation, based on a non-parametric estimate of the underlying error distribution. The bootstrap will be applied to an econometric equation describing the demand for energy by industry, to determine multi-period forecasting error and choose among competing specifications. The delta method for estimating forecast errors turns out to be too optimistic by a factor of 2.  相似文献   

3.
Summary The tryptophan uptake was inhibited considerably in tryptamine grown cells. This inhibition was due to feed-back inhibition and not to repression.The authors are greatful to Prof. V. V. Modi for his interest in this work. The award of research fellowship by M. S. University of Baroda to A. R. G. is greatfully acknowledged.  相似文献   

4.
Summary The effect of administering barbital sodium, phenobarbitone or butobartitone during pregnancy was investigated in rats. The study shows that these bartiturates affect the litter-size and retard the foetal growth markedly. The embryos produced are significantly undersized.Acknowledgments. The authors wish to express their gratitude to Prof. M. R. Rajasekar Setty for the encouragement received and CSIR, India, for the award of a Research Fellowship to A. V. Champakamalini.  相似文献   

5.
The goal of this paper is to use a new modelling approach to extract quantile-based oil and natural gas risk measures using quantile autoregressive distributed lag mixed-frequency data sampling (QADL-MIDAS) regression models. The analysis compares this model to a standard quantile auto-regression (QAR) model and shows that it delivers better quantile forecasts at the majority of forecasting horizons. The analysis also uses the QADL-MIDAS model to construct oil and natural gas prices risk measures proxying for uncertainty, third-moment dynamics, and the risk of extreme energy realizations. The results document that these risk measures are linked to the future evolution of energy prices, while they are linked to the future evolution of US economic growth.  相似文献   

6.
过江隧道穿越既有铁路的相互影响是一个难点.依托重庆长江隧道穿越襄渝铁路工程进行研究,研究结果表明:过江隧道施工对既有铁路两个方向地表沉降的影响都很小,最大值为2.549 mm,故受影响的既有铁路附近地层不需做特殊加固处理,但要加强监控;既有铁路对过江隧道结构安全性及洞周位移影响也较小,在列车荷载作用下结构最小安全系数为6.8,过江隧道结构仍是偏于安全的,故隧道结构可不作加固处理,只需加强监控.研究成果为保证既有铁路的正常运营及过江隧道的结构安全性提供了理论基础,并可为相似工程提供参考.  相似文献   

7.
The nonlinear free transverse vibrations of a nano-beam on simple supports are investigated based on nonlocal elasticity theory.The governing equation is proposed by considering geometric nonlinearity due to finite stretching of the beam.The method of multiple scales is applied to the governing equation to evaluate the nonlinear natural frequencies.Numerical examples are presented to demonstrate the analytical results and highlight the contributions of the nonlinear term and nonlocal effect.  相似文献   

8.
The band density profile of a marked chromosome was obtained using a photodiode collector combined with a minicalculator, working with an ordinary photographic document. The measurement was carried out over 10 to 20 300-point lines oriented longitudinally along the chromosome. The profile obtained corresponds to the sum of the values of each of these lines. The proposed systems's originality resides in its ability to determine the position and intensity of a band over the entire thickness of the chromosome.  相似文献   

9.
The spectrum of a chromophore may change as a result of perturbations in its environment. The spectral changes resulting from the perturbation are often followed by measurements at just one or two wavelengths but it is usually no more difficult to collect entire spectra. The problem comes in analysing the data from such a series of spectra. In this paper we will suggest a simple procedure in which the spectrum observed under any particular set of conditions may be considered to consist of the sum of two distinct spectral forms. The method, which is free of any assumptions regarding the quantitative relationship between the perturbation and the extent of spectral change, defines any given spectrum in terms of an apparent molar fraction of the contributing spectral forms. The variation of this apparent molar fraction provides information from which a quantitative relationship can be developed to describe the dependence of the spectral change on the perturbant. The method is illustrated using the model system of phenol red protonation and is applied to the characterization of the binding of azide ions to cobalt-substituted carbonic anhydrase.  相似文献   

10.
Regulation of flowering time: all roads lead to Rome   总被引:5,自引:0,他引:5  
Plants undergo a major physiological change as they transition from vegetative growth to reproductive development. This transition is a result of responses to various endogenous and exogenous signals that later integrate to result in flowering. Five genetically defined pathways have been identified that control flowering. The vernalization pathway refers to the acceleration of flowering on exposure to a long period of cold. The photoperiod pathway refers to regulation of flowering in response to day length and quality of light perceived. The gibberellin pathway refers to the requirement of gibberellic acid for normal flowering patterns. The autonomous pathway refers to endogenous regulators that are independent of the photoperiod and gibberellin pathways. Most recently, an endogenous pathway that adds plant age to the control of flowering time has been described. The molecular mechanisms of these pathways have been studied extensively in Arabidopsis thaliana and several other flowering plants.  相似文献   

11.
Since growth curves are often used to produce medium- to long-term forecasts for planning purposes, it is obviously of value to be able to associate an interval with the forecast trend. The problems in producing prediction intervals are well described by Chatfield. The additional problems in this context are the intrinsic non-linearity of the estimation procedure and the requirement for a prediction region rather than a single interval. The approaches considered are a Taylor expansion of the variance of the forecast values, an examination of the joint density of the parameter estimates, and bootstrapping. The performance of the resultant intervals is examined using simulated data sets. Prediction intervals for real data are produced to demonstrate their practical value.  相似文献   

12.
The hoatzin is the only bird known to have pregastric fermentation in the crop. This digestive strategy is supported by morphological and microbiological adaptations analogous to those present in ruminants and ruminant-like mammals. The hoatzin expresses a lysozyme-like bacteriolytic activity in its foregut. The enzyme has a high activity, and its low pH optimum, pepsin resistance and localization to the proventriculus allow it to be active for digestion in the stomach. The hoatzin enzyme and the ruminant gastric lysozyme present similar biochemical characteristics. The lysis of bacterial cells may be of significance for the nutrition of the hoatzin. We propose that the hoatzin expresses a lysozyme which has been recruited to function as a digestive enzyme, representing a unique case of evolutionary convergence of digestive adaptations in this bird and foregut fermenter mammals.  相似文献   

13.
The study of forecasting techniques has received increased attention in recent years. How to incorporate this topic into the business school curriculum is a frequent subject of discussion. The purpose of this study was to determine whether forecasting is being taught in business schools and how it is incorporated into the curriculum. The survey instrument was sent to 622 member institutions of the American Assembly of Collegiate schools of Business. The importance of teaching forecasting techniques at both the undergraduate and graduate level was investigated.  相似文献   

14.
The levels of beta-trace protein and lysozyme were estimated in amniotic fluids from normal fetuses and from fetuses with neuraltube defects. The values of these proteins in normal amniotic fluids were found to be similar to those detected in fetuses with anencephaly and spina bifida. The levels of lysozyme were shown to be correlated with gestational age.  相似文献   

15.
Summary The drug Ro 7-1051 showed a deleterious effect on the intracellular and extracellular forms of Trypanosoma cruzi represented by nuclear pyknosis, fragmentation and lysis of parasites and by its reduced susceptibility to infection.Acknowledgments. The authors are deeply thankful to Roche Products for supplying the drug and for valuable information. The authors are also grateful to Prof. Nelson Villa for criticism and to Miss edna Bertin for technical assistance  相似文献   

16.
T A McCalden  M Levy 《Experientia》1990,46(7):713-715
The ability of liposomes composed of different kinds of phospholipid materials to adhere to the surface of the cornea was studied in the rabbit. The liposomes were labelled with tracer amounts of an I125-labelled phosphatidylethanolamine derivative and were instilled in 10 microliters drops onto the cornea. The retention of radioactivity was monitored. The results show that liposomes containing positively charged phospholipids are better retained than an albumin control. Thus, it may be possible to develop a drug delivery liposome system which would permit long-term sustained release of ophthalmic drugs onto the cornea.  相似文献   

17.
This paper considers the problem of forecasting high‐dimensional time series. It employs a robust clustering approach to perform classification of the component series. Each series within a cluster is assumed to follow the same model and the data are then pooled for estimation. The classification is model‐based and robust to outlier contamination. The robustness is achieved by using the intrinsic mode functions of the Hilbert–Huang transform at lower frequencies. These functions are found to be robust to outlier contamination. The paper also compares out‐of‐sample forecast performance of the proposed method with several methods available in the literature. The other forecasting methods considered include vector autoregressive models with ∕ without LASSO, group LASSO, principal component regression, and partial least squares. The proposed method is found to perform well in out‐of‐sample forecasting of the monthly unemployment rates of 50 US states. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

18.
The involvement of heat shock proteins in immune response is categorized into four distinct paradigms. In the First Paradigm, HSP derived from foreign organisms act as classical foreign antigens, and they elicit immune response to the non-conserved HSP epitopes. The Second Paradigm refers to instances where the host responds to self HSP to which there is no central or peripheral tolerance. The Third Paradigm involves molecular mimicry, where cross-reactivity between an HSP and another protein leads to an immune response to the latter under conditions which elicit an immune response to the former, such as infection with a bacterium whose immunodominant antigen is an HSP. The Fourth Paradigm refers to situations where an HSP-antigen complex elicits an effective response to the antigen andnot to the HSP. Thus the HSP acts as a carrier for the antigenic peptide. The role of HSP in recognition by γδ T cells may also fall into this paradigm. In this article, the Fourth Paradigm is considered as a crucial element in the development of vaccines against cancers and infectious diseases, and is analyzed through the prism of the observed association of hsp70 species with antigenic peptides.  相似文献   

19.
Summary The spectrum of a chromophore may change as a result of perturbations in its environment. The spectral changes resulting from the perturbation are often followed by measurements at just one or two wavelengths but it is usually no more difficult to collect entire spectra. The problem comes in analysing the data from such a series of spectra. In this paper we will suggest a simple procedure in which the spectrum observed under any particular set of conditions may be considered to consist of the sum of two distinct spectral forms. The method, which is free of any assumptions regarding the quantitative relationship between the perturbation and the extent of spectral change, defines any given spectrum in terms of an apparent molar fraction of the contributing spectral forms. The variation of this apparent molar fraction provides information from which a quantitative relationship can be developed to describe the dependence of the spectral change on the perturbant. The method is illustrated using the model system of phenol red protonation and is applied to the characterization of the binding of azide ions to cobalt-substituted carbonic anhydrase.  相似文献   

20.
The 111 series of the Makridakis competition are used to address a number of questions pertaining to use of the Box–Jenkins technique. The ARIMA models developed are compared to the ARIMA models developed independently by Andersen for the Makridakis competition. The time required to perform the analysis for each series is discussed in terms of model complexity. Forecast accuracy, measured as the MAPE for the one step ahead forecast, is discussed for different series lengths.  相似文献   

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