نتایج جستجو برای: nonlinear models

تعداد نتایج: 1095301  

Extended abstract Introduction: Germination speed is one of the most important germination indices, which is used in the most studies to compare the effects of different treatments on germination of seeds. Researchers use the reverse time to 50% maximum germination (1/D50) to calculate the germination rate. One of the methods for calculating the D50 is the use of nonlinear regression models s...

Journal: Iranian Economic Review 2007

Modeling and analysis of future prices has been hot topic for economic analysts in recent years. Traditionally, the complex movements in the prices are usually taken as random or stochastic process. However, they may be produced by a deterministic nonlinear process. Accuracy and efficiency of economic models in the short period forecasting is strategic and crucial for business world. Nonlinear ...

Journal: :مهندسی صنایع 0
مهدی خاشعی مهندسی صنایع مهدی بیجاری مهندسی صنایع غلامعلی رئیسی اردلی مهندسی صنایع

time series forecasting is an active research area that has drawn considerable attention for applications in a variety of areas. forecasting accuracy is one of the most important features of forecasting models. nowadays, despite the numerous time series forecasting models which have been proposed in several past decades, it is widely recognized that financial markets are extremely difficult to ...

Journal: :مرتع و آبخیزداری 0
ام البنین بذرافشان استادیار دانشکدة منابع طبیعی دانشگاه هرمزگان علی سلاجقه دانشیار دانشکدة کشاورزی و منابع طبیعی دانشگاه تهران احمد فاتحی مرج استادیار مرکز تحقیقات کم آبی و خشک سالی در کشاورزی و منابع طبیعی، تهران محمد مهدوی استاد دانشکدة کشاورزی و منابع طبیعی دانشگاه تهران جواد بذرافشان استادیار دانشکدة کشاورزی و منابع طبیعی دانشگاه تهران سمیه حجابی دانشجوی دکتری دانشکدة کشاورزی و منابع طبیعی دانشگاه تهران

drought is random and nonlinear phenomenon and using linear stochastic models, nonlinear artificial neural network and hybrid models is advantaged for drought forecasting. this paper presents the performances of autoregressive integrated moving average (arima), direct multi-step neural network (dmsnn), recursive multi-step neural network (rmsnn), hybrid stochastic neural network of directive ap...

Journal: Iranian Economic Review 2004

Applying nonlinear models to estimation and forecasting economic models are now becoming more common, thanks to advances in computing technology. Artificial Neural Networks (ANN) models, which are nonlinear local optimizer models, have proven successful in forecasting economic variables. Most ANN models applied in Economics use the gradient descent method as their learning algorithm. However, t...

Journal: :journal of agricultural science and technology 2014
m. r. bahreini behzadi a. a. aslaminejad a. r. sharifi h. simianer

the objectives of this study were to identify a suitable mathematical model for describing the growth curve of baluchi sheep based on monthly records of live weight from birth to yearling; and to evaluate the efficacies of nonlinear mixed effect model (nlmm) and the nonlinear fixed effect model (nlm) methodologies. growth models were fitted to a total of 16,650 weight–age data belonging to 2071...

Journal: :iranian journal of fuzzy systems 2015
bhupendra kumar pathak sanjay srivastava

this study presents the effects of project uncertainties on nonlinear time-cost tradeoff (tct) profile of real life engineering projects by the fusion of fuzzy logic and artificial neural network (ann) models with hybrid meta-heuristic (hmh) technique, abridged as fuzzy-ann-hmh. nonlinear time-cost relationship of project activities is dealt with ann models. ann models are then integrated with ...

M. Zohrehbandian S. Borzoei

In this paper, by investigating the common weights concept and DEA models with nonlinear virtual inputs/outputs, we introduce a model for evaluating the decision making units with nonlinear virtual inputs and outputs based on the common weights.

Extended abstract   Introduction: Numerous studies are being carried out to reveal the effects of different treatments on the germination of seeds from various plants. The most commonly used method of analysis is the nonlinear regression which estimates germination parameters. Although the nonlinear regression has been performed based on different models, some serious problems in its structure...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید