Academic literature on the topic 'GWO TECHNIQUE'

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Journal articles on the topic "GWO TECHNIQUE"

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Mousa, M. E., M. A. Ebrahim, Magdy M. Zaky, E. M. Saied, and S. A. Kotb. "Hybrid Optimization Technique for Enhancing the Stability of Inverted Pendulum System." International Journal of Swarm Intelligence Research 12, no. 1 (January 2021): 77–97. http://dx.doi.org/10.4018/ijsir.2021010105.

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The inverted pendulum system (IPS) is considered the milestone of many robotic-based industries. In this paper, a new variant of variable structure adaptive fuzzy (VSAF) is used with new reduced linear quadratic regulator (RLQR) and feedforward gain for enhancing the stability of IPS. The optimal determining of VSAF parameters as well as Q and R matrices of RLQR are obtained by using a modified grey wolf optimizer with adaptive constants property via particle swarm optimization technique (GWO/PSO-AC). A comparison between the hybrid GWO/PSO-AC and classical GWO/PSO based on multi-objective function is provided to justify the superiority of the proposed technique. The IPS equipped with the hybrid GWO/PSO-AC-based controllers has minimum settling time, rise time, undershoot, and overshoot results for the two system outputs (cart position and pendulum angle). The system is subjected to robustness tests to ensure that the system can cope with small as well as significant disturbances.
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Nsour, Heba Al, Mohammed Alweshah, Abdelaziz I. Hammouri, Hussein Al Ofeishat, and Seyedali Mirjalili. "A Hybrid Grey Wolf Optimiser Algorithm for Solving Time Series Classification Problems." Journal of Intelligent Systems 29, no. 1 (July 31, 2018): 846–57. http://dx.doi.org/10.1515/jisys-2018-0129.

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Abstract One of the major objectives of any classification technique is to categorise the incoming input values based on their various attributes. Many techniques have been described in the literature, one of them being the probabilistic neural network (PNN). There were many comparisons made between the various published techniques depending on their precision. In this study, the researchers investigated the search capability of the grey wolf optimiser (GWO) algorithm for determining the optimised values of the PNN weights. To the best of our knowledge, we report for the first time on a GWO algorithm along with the PNN for solving the classification of time series problem. PNN was used for obtaining the primary solution, and thereby the PNN weights were adjusted using the GWO for solving the time series data and further decreasing the error rate. In this study, the main goal was to investigate the application of the GWO algorithm along with the PNN classifier for improving the classification precision and enhancing the balance between exploitation and exploration in the GWO search algorithm. The hybrid GWO-PNN algorithm was used in this study, and the results obtained were compared with the published literature. The experimental results for six benchmark time series datasets showed that this hybrid GWO-PNN outperformed the PNN algorithm for the studied datasets. It has been seen that hybrid classification techniques are more precise and reliable for solving classification problems. A comparison with other algorithms in the published literature showed that the hybrid GWO-PNN could decrease the error rate and could also generate a better result for five of the datasets studied.
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Nahak, Narayan, and Ranjan Kumar Mallick. "Efficacy of GWO Optimized PI and Lead-lag Controller for Design of UPFC based Supplementary Damping Controller." IAES International Journal of Robotics and Automation (IJRA) 6, no. 4 (December 1, 2017): 241. http://dx.doi.org/10.11591/ijra.v6i4.pp241-251.

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<p><span>On line tuning of FACTS based damping controller is a vital decisive task in power system. In this regard two things need to be addressed, one is selection of a proper controller and another one is selection of a powerful optimization technique. In this work Grey Wolf Optimizer (GWO) technique is proposed to tune parameters of PI and lead lag controller based on UPFC to damp intra plant and inter area electromechanical oscillations with single and multi machine power system. A broad comparison has been performed with eigen value analysis between optimized PI and lead lag damping controller subject to different disturbances in power system. The recently revealed GWO, standard PSO and DE techniques are explicitly employed to tune UPFC based PI and lead-lag controller parameters. The system response predicts that performance of GWO is much better than PSO and DE techniques, and also lead lag controller is a better choice than PI controller pertaining to design of UPFC based damping controller.</span></p>
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Badi, Manjulata, Sheila Mahapatra, Bishwajit Dey, and Saurav Raj. "A Hybrid GWO-PSO Technique for the Solution of Reactive Power Planning Problem." International Journal of Swarm Intelligence Research 13, no. 1 (January 2022): 1–30. http://dx.doi.org/10.4018/ijsir.2022010104.

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Over the years the optimization in various areas of power system has immensely attracted the attention of power engineers and researchers. RPP problem is one of such areas. This is done by the placement of reactive power sources in the weak buses and thereafter minimizing the operating cost of the system which is directly dependent on the system transmission loss. The work proposed in this article utilizes FVSI method to detect the weak bus. GWO-PSO is proposed in the current work for providing optimal solution to RPP problem. To test the efficacy of the proposed technique, comparative analysis is then performed among the variants of PSO and hybrid GWO-PSO. The optimal solution rendered by the proposed method is compared with other heuristic algorithms. The proposed method of GWO-PSO generates a reduction of 4.25% in operating cost for IEEE 30 bus and 5.99% for New England 39 bus system. The comparison thus yields that the GWO-PSO hybrid method is superior in generating optimality, diversity and is efficient to generate solution strategies for RPP even in a practical power network.
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Mat Yasin, Zuhaila, Nur Ashida Salim, Nur Fadilah Ab Aziz, Hasmaini Mohamad, and Norfishah Ab Wahab. "Prediction of solar irradiance using grey wolf Optimizer-Least-Square support vector machine." Indonesian Journal of Electrical Engineering and Computer Science 17, no. 1 (January 1, 2020): 10. http://dx.doi.org/10.11591/ijeecs.v17.i1.pp10-17.

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<span>Prediction of solar irradiance is important for minimizing energy costs and providing high power quality in a photovoltaic (PV) system. This paper proposes a new technique for prediction of hourly-ahead solar irradiance namely Grey Wolf Optimizer- Least-Square Support Vector Machine (GWO-LSSVM). Least Squares Support Vector Machine (LSSVM) has strong ability to learn a complex nonlinear problems. In GWO-LSSVM, the parameters of LSSVM are optimized using Grey Wolf Optimizer (GWO). GWO algorithm is derived based on the hierarchy of leadership and the grey wolf hunting mechanism in nature. The main step of the grey wolf hunting mechanism are hunting, searching, encircling, and attacking the prey. The model has four input vectors: time, relative humidity, wind speed and ambient temperature. Mean Absolute Performance Error (MAPE) is used to measure the prediction performance. Comparative study also carried out using LSSVM and Particle Swarm Optimizer-Least Square Support Vector Machine (PSO-LSSVM). The results showed that GWO-LSSVM predicts more accurate than other techniques. </span>
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Sulttan, Mohammed Qasim, Salam Waley Shneen, and Jafaar Mohammed Daif Alkhasraji. "Performance enhancement of large-scale linear dynamic MIMO systems using GWO-PID controller." Bulletin of Electrical Engineering and Informatics 12, no. 5 (October 1, 2023): 2852–59. http://dx.doi.org/10.11591/eei.v12i5.4870.

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The multi-input multi-output (MIMO) technique is becoming grown and integrated into wireless wideband communication. MIMO techniques suffer from a large-scale linear dynamic problem, it will be easy to adjust the proportional-integral-derivative (PID) of a continuous system, unlike the nonlinear model. This work displays the tuning of the PID controller for MIMO systems utilizing a statistical grey wolf optimization (GWO) and evaluated by objective function as integral time absolute error (ITAE). The instantaneous adjusting characteristic GWO approach is the criterion that distinguishes such a combination-proposed strategy from that existing in the traditional PID approach. The GWO algorithm searching-based methodology is used to determine the adequate gain factors of the PID controller. The suggested approach guarantees stability as the initial scheme for a steady state condition. A combination of ITAE combined with the GWO reduction method is adopted to reduce the steady-state transient time responses between the higher-order initial scheme and the unit amplitude response. Simulation outcomes are illustrated using MATLAB software to show the capability of adopting the GWO scheme for PID controlling.
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Putri, Ajeng Maharani, Zuherman Rustam, Jacub Pandelaki, Ilsya Wirasati, and Sri Hartini. "Acute sinusitis data classification using grey wolf optimization-based support vector machine." IAES International Journal of Artificial Intelligence (IJ-AI) 10, no. 2 (June 1, 2021): 438. http://dx.doi.org/10.11591/ijai.v10.i2.pp438-445.

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<span id="docs-internal-guid-ebf19048-7fff-9350-093e-7f1e8df23393"><span>Acute sinusitis is the most common form of sinusitis, and it causes swelling and inflammation within the nose. The main thing that can causes sinusitis is probably due to viruses, and also can be caused by other factors, namely bacteria, fungi, irritation, dust, and allergens. In this research, the CT scan data attributes will be used for classification and grey wolf optimization-support vector machine (GWO-SVM) will be the machine learning technique used, where the GWO technique will be used to tuned the parameters in SVM. The performance of methods was analyzed using the python programming language with different percentages of training data, which started from 10% to 90%. The GWO-SVM method proposed provides better accuracy than using SVM without GWO.</span></span>
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Roy, Provas Kumar, Moumita Pradhan, and Tandra Pal. "Multi-Objective Hydro-Thermal Scheduling Problem Using Two Novel Optimization Techniques." International Journal of Swarm Intelligence Research 12, no. 3 (July 2021): 1–36. http://dx.doi.org/10.4018/ijsir.2021070101.

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This article describes an efficient and reliable strategy for the scheduling of nonlinear multi-objective hydrothermal power systems using the grey wolf optimization (GWO) technique. Moreover, the theory of oppositional-based learning (OBL) is integrated with original GWO for further enhancing its convergence rate and solution accuracy. The constraints related to hydro and thermal plants and environmental aspects are also considered in this paper. To show its efficiency and effectiveness, the proposed GWO and OGWO algorithms are authenticated for the test system consisting of a multi-chain cascade of 4 hydro and 3 thermal units whose valve-point loading effects are also taken into account. Furthermore, statistical outcomes of the conventional heuristic approaches available in the literature are compared with the proposed GWO and OGWO approaches, and these methods give moderately better operational fuel cost and emission in less computational time.
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Yan, Fu, Jianzhong Xu, and Kumchol Yun. "Dynamically Dimensioned Search Grey Wolf Optimizer Based on Positional Interaction Information." Complexity 2019 (December 5, 2019): 1–36. http://dx.doi.org/10.1155/2019/7189653.

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The grey wolf optimizer (GWO) algorithm is a recently developed, novel, population-based optimization technique that is inspired by the hunting mechanism of grey wolves. The GWO algorithm has some distinct advantages, such as few algorithm parameters, strong global optimization ability, and ease of implementation on a computer. However, the paramount challenge is that there are some cases where the GWO is prone to stagnation in local optima. This drawback of the GWO algorithm may be attributed to an insufficiency in its position-updated equation, which disregards the positional interaction information about the three best grey wolves (i.e., the three leaders). This paper proposes an improved version of the GWO algorithm that is based on a dynamically dimensioned search, spiral walking predation technique, and positional interaction information (referred to as the DGWO). In addition, a nonlinear control parameter strategy, i.e., the control parameter that is nonlinearly increased with an increase in iterations, is designed to balance the exploration and exploitation of the GWO algorithm. The experimental results for 23 general benchmark functions and 3 well-known engineering optimization design applications validate the effectiveness and feasibility of the proposed DGWO algorithm. The comparison results for the 23 benchmark functions show that the proposed DGWO algorithm performs significantly better than the GWO and its improved variant for most benchmarks. The DGWO provides the highest solution precision, strongest robustness, and fastest convergence rate among the compared algorithms in almost all cases.
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Oliveira, Josenalde, Paulo Moura Oliveira, José Boaventura-Cunha, and Tatiana Pinho. "Evaluation of Hunting-Based Optimizers for a Quadrotor Sliding Mode Flight Controller." Robotics 9, no. 2 (April 7, 2020): 22. http://dx.doi.org/10.3390/robotics9020022.

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The design of Multi-Input Multi-Output nonlinear control systems for a quadrotor can be a difficult task. Nature inspired optimization techniques can greatly improve the design of non-linear control systems. Two recently proposed hunting-based swarm intelligence inspired techniques are the Grey Wolf Optimizer (GWO) and the Ant Lion Optimizer (ALO). This paper proposes the use of both GWO and ALO techniques to design a Sliding Mode Control (SMC) flight system for tracking improvement of altitude and attitude in a quadrotor dynamic model. SMC is a nonlinear technique which requires that its strictly coupled parameters related to continuous and discontinuous components be correctly adjusted for proper operation. This requires minimizing the tracking error while keeping the chattering effect and control signal magnitude within suitable limits. The performance achieved with both GWO and ALO, considering realistic disturbed flight scenarios are presented and compared to the classical Particle Swarm Optimization (PSO) algorithm. Simulated results are presented showing that GWO and ALO outperformed PSO in terms of precise tracking, for ideal and disturbed conditions. It is shown that the higher stochastic nature of these hunting-based algorithms provided more confidence in local optima avoidance, suggesting feasibility of getting a more precise tracking for practical use.
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Dissertations / Theses on the topic "GWO TECHNIQUE"

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Cruz, Shane Elliot 1979. "An investigation into better techniques for geo-targeting." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/87222.

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Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2002.
Includes bibliographical references (p. 81-84).
by Shane Elliot Cruz.
M.Eng.
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Picavet, Paul. "Les meules rotatives de la fin de l'Âge du Fer au haut Moyen Âge entre la Seine et le Rhin." Thesis, Lille, 2019. http://www.theses.fr/2019LIL3H005.

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Les meules, pièces maîtresses et les mieux conservées des moulins, sont emblématiques des questions relatives à l’histoire de l’économie et des techniques.De l’économie, parce que l’analyse des roches meulières révèle une chaîne complexe de recherche des ressources, d’extraction, de mise en forme, de distribution et d’utilisation qui dépend d’une série de facteurs qui ne concernent pas seulement les meules mais peuvent s’appliquer à toutes sortes de productions artisanales répondant à des besoins primaires de subsistance.Des techniques, parce que l’amélioration des procédés de mouture est le fruit d’une transmission des savoir-faire techniques alliée à une recherche constante de la meilleure réponse possible à des besoins alimentaires qui eux-mêmes évoluent. Cette notion de progrès technique, que l’on observe à la fois sur le temps long (ici plus d’un millénaire) et à l’occasion de brèves transitions politico-culturelles (la conquête romaine de la Gaule puis les migrations germaniques), est à l’origine de profonds changements socio-économiques.Sur la base de travaux de terrain (prospections thématiques), d’analyses d’objets (les meules) et d’un tour d’horizon bibliographique, cette thèse présente une synthèse régionale sur un type de mobilier modeste mais structurant des sociétés et des économies anciennes
Millstones, as the centerpieces and the best preserved elements of mills, are characteristic of the questions relating to the history of techniques and economics.Of economics, because analysis of the rocks from which they are made reveal a complex chain including their research, extraction, shaping, distribution and use. The factors on which this chain depends don’t only concern querns and millstones but can be applied to all types of craft production that answer to primary needs of subsistence.Of techniques because the improving of milling processes is due to a transmission of technical savoir-faire, mixed with a constant research for the best solution to evolving food needs. This notion of technical progress is observed both over a long time scale (1000 years) and during brief political and cultural transitions (the Roman conquest of Gaul, and the Germanic migrations). This evolution is the basis of deep social and economic changes.Based on field surveys, artifact analysis (querns and millstones) and a literature survey, this thesis presents a regional synthesis on a modest but structuring element of ancient societies and their economies
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Gao, Mengfei [Verfasser]. "Combining expansion microscopy with other super-resolution techniques / Mengfei Gao." Berlin : Freie Universität Berlin, 2020. http://d-nb.info/1205314776/34.

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Chini, Marco <1973&gt. "Radar and optical remote sensing techniques for earthquake damage mapping." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/863/1/Tesi_Chini_Marco.pdf.

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Chini, Marco <1973&gt. "Radar and optical remote sensing techniques for earthquake damage mapping." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/863/.

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Ferrara, Carlotta <1983&gt. "Ground penetrating radar early-time technique for soil electromagnetic parameters estimation." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6311/1/Ferrara_Carlotta_Tesi.pdf.

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In recent years, thanks to the technological advances, electromagnetic methods for non-invasive shallow subsurface characterization have been increasingly used in many areas of environmental and geoscience applications. Among all the geophysical electromagnetic methods, the Ground Penetrating Radar (GPR) has received unprecedented attention over the last few decades due to its capability to obtain, spatially and temporally, high-resolution electromagnetic parameter information thanks to its versatility, its handling, its non-invasive nature, its high resolving power, and its fast implementation. The main focus of this thesis is to perform a dielectric site characterization in an efficient and accurate way studying in-depth a physical phenomenon behind a recent developed GPR approach, the so-called early-time technique, which infers the electrical properties of the soil in the proximity of the antennas. In particular, the early-time approach is based on the amplitude analysis of the early-time portion of the GPR waveform using a fixed-offset ground-coupled antenna configuration where the separation between the transmitting and receiving antenna is on the order of the dominant pulse-wavelength. Amplitude information can be extracted from the early-time signal through complex trace analysis, computing the instantaneous-amplitude attributes over a selected time-duration of the early-time signal. Basically, if the acquired GPR signals are considered to represent the real part of a complex trace, and the imaginary part is the quadrature component obtained by applying a Hilbert transform to the GPR trace, the amplitude envelope is the absolute value of the resulting complex trace (also known as the instantaneous-amplitude). Analysing laboratory information, numerical simulations and natural field conditions, and summarising the overall results embodied in this thesis, it is possible to suggest the early-time GPR technique as an effective method to estimate physical properties of the soil in a fast and non-invasive way.
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Ferrara, Carlotta <1983&gt. "Ground penetrating radar early-time technique for soil electromagnetic parameters estimation." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6311/.

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In recent years, thanks to the technological advances, electromagnetic methods for non-invasive shallow subsurface characterization have been increasingly used in many areas of environmental and geoscience applications. Among all the geophysical electromagnetic methods, the Ground Penetrating Radar (GPR) has received unprecedented attention over the last few decades due to its capability to obtain, spatially and temporally, high-resolution electromagnetic parameter information thanks to its versatility, its handling, its non-invasive nature, its high resolving power, and its fast implementation. The main focus of this thesis is to perform a dielectric site characterization in an efficient and accurate way studying in-depth a physical phenomenon behind a recent developed GPR approach, the so-called early-time technique, which infers the electrical properties of the soil in the proximity of the antennas. In particular, the early-time approach is based on the amplitude analysis of the early-time portion of the GPR waveform using a fixed-offset ground-coupled antenna configuration where the separation between the transmitting and receiving antenna is on the order of the dominant pulse-wavelength. Amplitude information can be extracted from the early-time signal through complex trace analysis, computing the instantaneous-amplitude attributes over a selected time-duration of the early-time signal. Basically, if the acquired GPR signals are considered to represent the real part of a complex trace, and the imaginary part is the quadrature component obtained by applying a Hilbert transform to the GPR trace, the amplitude envelope is the absolute value of the resulting complex trace (also known as the instantaneous-amplitude). Analysing laboratory information, numerical simulations and natural field conditions, and summarising the overall results embodied in this thesis, it is possible to suggest the early-time GPR technique as an effective method to estimate physical properties of the soil in a fast and non-invasive way.
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Chen, Weiyi. "L'hétérogénéisation et l'altérité : Guo Xi, Giuseppe Castiglione et Xu Baihong. Ou la modification dans la peinture chinoise." Thesis, Université de Paris (2019-....), 2019. http://www.theses.fr/2019UNIP7007.

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Les images, les peintures montrent davantage ce qu’il y a d’inattendu, de surprenant dans la pensée de l’autre, elles nous aident à voir et à comprendre l’altérité. Cette recherche se présente comme une rétrospective de la transformation de la pensée chinoise à travers les œuvres de trois peintres qui sembleraient marquer des jalons dans l’histoire d’une rencontre avec l’autre : Guo Xi, Giuseppe Castiglione et Xu Beihong. Les œuvres nous serviront d’appui pour discuter sur la culture et sa transformation. Dans ce sens Guo Xi nous permettra de discuter sur l’altérité de la peinture et la pensée chinoises, Giuseppe Castiglione et Xu Beihong nous aideront à montrer comment la peinture européenne, qui est un autre pour la Chine, a transformé le champ visuel en Chine. Pourtant, une rétrospective est inévitablement anachronique : en essayant de situer les peintres dans leur époque, nous les voyons toujours à partir de la situation actuelle. Mais cet anachronisme fait en même temps tout l’intérêt d’une recherche qui a pour objectif de décrire la rencontre, l’hétérogénéisation et la globalisation comme un processus dans la durée. L’hétérogénéisation est comprise comme un enrichissement incessant au sein de la culture et la globalisation est comprise comme un processus où les cultures, chinoise et européenne, se trouvent en confrontation l’une avec l’autre. Ces deux termes sont les facettes de la rencontre entre la Chine et l’Occident, qui a marqué profondément l’histoire moderne et qui est toujours en train de se réaliser. L’objectif de ce travail est de montrer par où la Chine entre dans ce processus de la globalisation et de montrer l’issue intermédiaire de la confrontation de la peinture chinoise avec la peinture européenne
The images, paintings show what is unexpected, surprising in the thought of the other, they help us to see and understand otherness. This research presents itself as a retrospective of the transformation of the Chinese thought through the works of three painters who seem to mark milestones in the history of encountering with the other: Guo Xi, Giuseppe Castiglione and Xu Beihong. The artworks serve as support for the discussion of culture and its transformation. In this sense Guo Xi will allow us to discuss the otherness of the Chinese painting and thought, Giuseppe Castiglione and Xu Beihong will help us to show how the European painting, which is the other for China, has transformed the visual field in China. However, a retrospective is inevitably anachronistic: by trying to locate painters in their own context, we always see them from the current situation. But this anachronism is at the same time the very point of interest of the research that aims to describe the encounter, heterogenization and globalisation as a long-term process. Heterogenization is understood as an enrichment of culture and globalisation is understood as a process in which cultures, Chinese and European, are in confrontation with one another. These two terms are the facets of the encounter between China and the West, which has profoundly affected modern history and is still ongoing. The objective of this work is to show where China is entering this process of globalisation and show the intermediate outcome of the confrontation of the Chinese painting with the European painting
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Ferrari, F. "ROCK MASS CHARACTERIZATION AND SPATIAL ESTIMATION OF GEOMECHANICAL PROPERTIES THROUGH GEOSTATISTICAL TECHNIQUES." Doctoral thesis, Università degli Studi di Milano, 2014. http://hdl.handle.net/2434/231572.

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This thesis deals with geostatistics, which is a branch of statistics focusing on spatial or spatiotemporal datasets, and explores its possible application to rock mechanics, with particular reference to wide areas, located in the Alpine context. The final objective of this work is the estimation (i.e. the prediction), through geostatistical techniques, of the geomechanical parameters determining the quality of rock masses, starting form punctual and scattered sampling locations.This thesis is a contribute in assessing how the rock mass features, in the Alpine geological context, can be regarded as regionalized variables, and the geostatistical tool can be used to foresee the spatial structure of rock masses. The main topic regards the estimation of rock mass properties, and their associated variations, at regional scale, through geostatistical techniques. The estimation consists in forecasting the behaviour and the values of a regionalized variable, in an area, starting form punctual and scattered measures. The main challenge is to understand if the geostatistical techniques, applied so successfully to local and specific problems, can be applied also at regional scale (i.e. considering very wide portion of territory), finding the best method useful to make estimation of that scale. Actually to have a tool able to predict the rock mass parameters at regional scale can be very useful in areas interested by the planning and construction of large-scale engineering works. The study areas, chosen to verify the applicability of geostatistical methods at regional scale, are both located in the Central Alps: the first is the Italian Alpine Valley named Valchiavenna (SO), while the second is in Switzerland, near the Grimselpass.The main innovative aspercts of this thesis, respect to the previous works, are: - the area involved in the estimations: very wide areas have been considered in order to verify if geostatistics give good results also at regional scale; - the geology of the site: hard rock masses outcropping on two different location of the Alpine chain have been investigated: the first one is in the Italian Central Alps and the second one in the Swiss Alps;- the starting measurements: data have been collected in situ using both direct and indirect measurements (i.e. geomechanical survey in Valchiavenna, combined with photogrammetric analysis at Grimsel test site).
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Adani, Mario <1977&gt. "Reanalysis Techniques for the numerical modelling of the Mediterranean Sea Circulation." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/861/1/Tesi_Adani_Mario.pdf.

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Books on the topic "GWO TECHNIQUE"

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Shen, Shuyang. Guo hua liu fa xin lun. [Beijing: Beijing zhong xian tuo fang ke ji fa zhan you xian gong si, 2007.

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Shen, Shuyang. Guo hua liu fa xin lun. [Beijing: Beijing zhong xian tuo fang ke ji fa zhan you xian gong si, 2012.

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Chinese Children Literature Collection (Library of Congress), ed. Guo hua. Nanjing Shi: Jiangsu shao nian er tong chu ban she, 2002.

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Chinese Children Literature Collection (Library of Congress), ed. Guo hua. Nanjing Shi: Jiangsu shao nian er tong chu ban she, 2003.

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Zhang Daqian ke tu gao. Zhengdu Shi: Sizhuan mei shu chu ban she, 1987.

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Xue guo hua. Chongqing: Chongqing chu ban she, 1999.

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Chinese Children Literature Collection (Library of Congress), ed. Guo hua. Nanjing Shi: Jiangsu shao nian er tong chu ban she, 2004.

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Roger, Hicks, ed. Te shu hisao guo she ying =: Photographic special effects. Xianggang: Wan li ji gou, wan li shu dian, 1997.

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Zhou, Shixin. Guo hua ji fa gai lun. Taibei Shi Yangmingshan Huagang: Zhongguo wen hua da xue chu ban bu, 1986.

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zhu, Du Zifang Bian, and Jiang, Yan Nu˜, 1973- Bian zhu, eds. Chou yang ji shu: Sampling technique. 4th ed. Beijing: Zhong guo ren min da xue chu ban she, 2015.

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Book chapters on the topic "GWO TECHNIQUE"

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Debnath, Manoj Kumar, and Priyambada Satapathy. "Mamdani-Based Fuzzy PI Controller Tuned by Binary GWO Technique for LFC Problem in Solar-Thermal Interconnected System." In Lecture Notes in Electrical Engineering, 79–90. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-6772-4_8.

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Gatrell, Jay D., Gregory D. Bierly, and Ryan R. Jensen. "Dissertation II: Geo-Techniques." In Research Design and Proposal Writing in Spatial Science, 125–43. Dordrecht: Springer Netherlands, 2011. http://dx.doi.org/10.1007/978-94-007-2281-1_13.

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Yu, Genong. "Dissertation II: Geo-Techniques." In Research Design and Proposal Writing in Spatial Science, 139–58. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-60019-8_13.

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Tripathi, Sandeep, Ashish Shrivastava, and K. C. Jana. "GWO Based PID Controller Optimization for Robotic Manipulator." In Intelligent Computing Techniques for Smart Energy Systems, 943–51. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-15-0214-9_100.

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Alkan, Reha Metin, I. Murat Ozulu, Veli İlçi, F. Engin Tombuş, and Murat Şahin. "Usability of GNSS Technique for Cadastral Surveying." In Cadastre: Geo-Information Innovations in Land Administration, 77–91. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-51216-7_8.

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Yang, Zhanwei, Yun Xu, Bo Cai, Liwei Wang, and Liao Wang. "Reducing Fracturing Pressure by Using Novel Stimulating Technique for Ultra-tight Rock." In Information Technology in Geo-Engineering, 460–67. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-32029-4_40.

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Weekes, Trevor C. "TeV Gamma-Ray Astronomy, Techniques." In The Gamma Ray Sky with Compton GRO and SIGMA, 27–38. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-011-0067-0_3.

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Potts, Philip J. "New Detection Techniques for Locating Precious Metal Minerals by Beta Autoradiography: Preliminary Results for Rhodium and Silver Grains." In Geo-Platinum 87, 47–56. Dordrecht: Springer Netherlands, 1988. http://dx.doi.org/10.1007/978-94-009-1353-0_7.

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Ouyang, Liu, Jinli Huang, Xiaohe Wu, and Bohu Yu. "Parallel Access Optimization Technique for Geographic Raster Data." In Geo-Informatics in Resource Management and Sustainable Ecosystem, 533–42. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-45025-9_52.

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Fang, Haifeng, Yachan Zhao, Rong Tan, and Tao Wang. "A Dynamic Switching Technique for Virtual Network in SDN Environment." In Geo-informatics in Sustainable Ecosystem and Society, 62–70. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-7025-0_6.

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Conference papers on the topic "GWO TECHNIQUE"

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Jayapriya, J., and Michael Arock. "A parallel GWO technique for aligning multiple molecular sequences." In 2015 International Conference on Advances in Computing, Communications and Informatics (ICACCI). IEEE, 2015. http://dx.doi.org/10.1109/icacci.2015.7275611.

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Sharma, Anushka, and Utkarsh Tyagi. "A Hybrid Approach of ANN-GWO Technique for Intrusion Detection." In 2021 International Conference on Recent Trends on Electronics, Information, Communication & Technology (RTEICT). IEEE, 2021. http://dx.doi.org/10.1109/rteict52294.2021.9573800.

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Deepika, Rajneesh Kumar, and Dalip. "An Enhanced Framework for Data Protection in Cloud Environment using ECL-GWO Technique." In 2023 International Conference on Innovative Data Communication Technologies and Application (ICIDCA). IEEE, 2023. http://dx.doi.org/10.1109/icidca56705.2023.10099650.

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Routray, Aliva, Khyati D. Mistry, and Sabharaj Arya. "Loss Minimization in Distribution System Considering Hourly Data Driven Probabilistic Solar Astronomical Model with GWO Technique." In 2019 IEEE 1st International Conference on Energy, Systems and Information Processing (ICESIP). IEEE, 2019. http://dx.doi.org/10.1109/icesip46348.2019.8938352.

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Merzoug, Ahmed, Abderraouf Chemmakh, Habib Ouadi, Aimen Laalam, Sofiane Djezzar, Aldjia Boualam, Nadia Mouedden, Vamegh Rasouli, and Ezdeen Ibrahim. "A New Model for Optimized Gas Allocation in Gas Lift Operation Using Metaheuristic Algorithms." In SPE Middle East Artificial Lift Conference and Exhibition. SPE, 2022. http://dx.doi.org/10.2118/206989-ms.

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Abstract Gas lift is one of the most commonly used artificial lift method in oil-producing wells. However, the technique requires constant optimization of gas allocation to maximize profit. The Gas Lift Performance Curves (GLPC) are the main design element that is used for optimized injection. Several authors have proposed models to fit the GLPC. These curves are generated by modeling wells in a multiphase steady-state simulator. Once the model is built, a sensitivity analysis is run, and the curves are generated. In this work, The common workflow to generate GLPC was followed. Then, a new correlation for GLPC was suggested. The correlation outperforms all the models in the literature in terms of R-score and root mean square error. The correlation was then used to formulate a case study for four wells located in North Africa. First, the wells and PVT models were used to create a simulation. Once the simulation was calibrated, a sensitivity analysis of the gas lift injection rate was run. The new correlation was used to fit the GLPC. The optimization problem was mathematically formulated, and stochastic optimization techniques were used, noting Grey Wolf Optimization (GWO) Algorithm and Genetic Algorithm (GA) to obtain the global optimum of the distribution of a limited gas lift quantity. Both algorithms’ results were compared. GWO slightly outperformed GA. The advantages of GWO over GA were discussed, and the optimum gas allocation was obtained.
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Wang, Manliang, and Bingtuan Gao. "An Improved GWO Technique Integrated with P&O Algorithm for Photovoltaic System Considering Different Conditions in the Irradiance." In 2022 IEEE 5th International Electrical and Energy Conference (CIEEC). IEEE, 2022. http://dx.doi.org/10.1109/cieec54735.2022.9846656.

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Debnath, Manoj Kumar, Manjit Bahadur Singh, and Ranjan Kumar Mallick. "Design of optimal 2-DOF PID controller using GWO technique for automatic generation control of a multisource power system." In 2016 IEEE Uttar Pradesh Section International Conference on Electrical, Computer and Electronics Engineering (UPCON). IEEE, 2016. http://dx.doi.org/10.1109/upcon.2016.7894710.

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Padhy, Sasmita, Rajendra Ku Khadanga, and Sidhartha Panda. "A modified GWO technique based fractional order PID controller with derivative filter coefficient for AGC of power systems with plug in electric vehicles." In 2018 Technologies for Smart-City Energy Security and Power (ICSESP). IEEE, 2018. http://dx.doi.org/10.1109/icsesp.2018.8376668.

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Suman, Swati, Debashis Chatterjee, and Rupali Mohanty. "Comparison of PSO and GWO Techniques for SHEPWM Inverters." In 2020 International Conference on Computer, Electrical & Communication Engineering (ICCECE). IEEE, 2020. http://dx.doi.org/10.1109/iccece48148.2020.9223108.

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Naudts, Alex, and Rudy Van Impe. "An Alternate Compaction Grouting Technique." In Geo-Denver 2000. Reston, VA: American Society of Civil Engineers, 2000. http://dx.doi.org/10.1061/40516(292)3.

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Reports on the topic "GWO TECHNIQUE"

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YANG, Wunian, Yulan WANG, Li PENG, Xianli HU, Min ZHANG, and Feng LIANG. Complicated Geo-Body Modeling Based on Dummy Borehole Chain Technique. Cogeo@oeaw-giscience, September 2011. http://dx.doi.org/10.5242/iamg.2011.0233.

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Cook, Samantha, Matthew Bigl, Sandra LeGrand, Nicholas Webb, Gayle Tyree, and Ronald Treminio. Landform identification in the Chihuahuan Desert for dust source characterization applications : developing a landform reference data set. Engineer Research and Development Center (U.S.), October 2022. http://dx.doi.org/10.21079/11681/45644.

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ERDC-Geo is a surface erodibility parameterization developed to improve dust predictions in weather forecasting models. Geomorphic landform maps used in ERDC-Geo link surface dust emission potential to landform type. Using a previously generated southwest United States landform map as training data, a classification model based on machine learning (ML) was established to generate ERDC-Geo input data. To evaluate the ability of the ML model to accurately classify landforms, an independent reference landform data set was created for areas in the Chihuahuan Desert. The reference landform data set was generated using two separate map-ping methodologies: one based on in situ observations, and another based on the interpretation of satellite imagery. Existing geospatial data layers and recommendations from local rangeland experts guided site selections for both in situ and remote landform identification. A total of 18 landform types were mapped across 128 sites in New Mexico, Texas, and Mexico using the in situ (31 sites) and remote (97 sites) techniques. The final data set is critical for evaluating the ML-classification model and, ultimately, for improving dust forecasting models.
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Холошин, Ігор Віталійович, Ірина Миколаївна Варфоломєєва, Олена Вікторівна Ганчук, Ольга Володимирівна Бондаренко, and Андрій Валерійович Пікільняк. Pedagogical techniques of Earth remote sensing data application into modern school practice. CEUR-WS.org, 2018. http://dx.doi.org/10.31812/123456789/3257.

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Abstract. The article dwells upon the Earth remote sensing data as one of the basic directions of Geo-Information Science, a unique source of information on processes and phenomena occurring in almost all spheres of the Earth geographic shell (atmosphere, hydrosphere, lithosphere, etc.). The authors argue that the use of aerospace images by means of the information and communication technologies involvement in the learning process allows not only to increase the information context value of learning, but also contributes to the formation of students’ cognitive interest in such disciplines as geography, biology, history, physics, computer science, etc. It has been grounded that remote sensing data form students’ spatial, temporal and qualitative concepts, sensory support for the perception, knowledge and explanation of the specifics of objects and phenomena of geographical reality, which, in its turn, provides an increase in the level of educational achievements. The techniques of aerospace images application into the modern school practice have been analyzed and illustrated in the examples: from using them as visual aids, to realization of practical and research orientation of training on the basis of remote sensing data. Particular attention is paid to the practical component of the Earth remote sensing implementation into the modern school practice with the help of information and communication technologies.
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Kholoshyn, Ihor V., Iryna M. Varfolomyeyeva, Olena V. Hanchuk, Olga V. Bondarenko, and Andrey V. Pikilnyak. Pedagogical techniques of Earth remote sensing data application into modern school practice. [б. в.], September 2019. http://dx.doi.org/10.31812/123456789/3262.

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The article dwells upon the Earth remote sensing data as one of the basic directions of Geo-Information Science, a unique source of information on processes and phenomena occurring in almost all spheres of the Earth geographic shell (atmosphere, hydrosphere, lithosphere, etc.). The authors argue that the use of aerospace images by means of the information and communication technologies involvement in the learning process allows not only to increase the information context value of learning, but also contributes to the formation of students’ cognitive interest in such disciplines as geography, biology, history, physics, computer science, etc. It has been grounded that remote sensing data form students’ spatial, temporal and qualitative concepts, sensory support for the perception, knowledge and explanation of the specifics of objects and phenomena of geographical reality, which, in its turn, provides an increase in the level of educational achievements. The techniques of aerospace images application into the modern school practice have been analyzed and illustrated in the examples: from using them as visual aids, to realization of practical and research orientation of training on the basis of remote sensing data. Particular attention is paid to the practical component of the Earth remote sensing implementation into the modern school practice with the help of information and communication technologies.
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Lozev and Spencer. L52023 Inspection of Welds in Thin-Wall Pipe Using Mechanized Ultrasonic Inspection. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), August 2003. http://dx.doi.org/10.55274/r0011117.

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Generally, the inspection of welds in pipes with a wall thickness less than 6 mm is performed using radiography.� Because radiography is very sensitive to the orientation of planar weld defects, these types of defects often go undetected.� In contrast, ultrasonic testing (UT) offers a better solution for detecting and sizing of these defects. In this project a method to inspect welds in thin-walled pipe less than 6-mm thick using mechanized ultrasonic weld inspection was developed.�The project investigated the application of time-based high-frequency (up to 15 MHz) single/multi-probe techniques and phased-array (PA) technology, multiple-skip time-of-flight diffraction (TOFD), and shear horizontal (SH) waves inspection as possible solutions.
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Gallagher, P. E. Stardate: NCGMP09 – to boldly go where no standard has gone before, DGGS Standards training (poster and presentation): Digital Mapping Techniques Workshop, Newark, Delaware, June 1-4, 2014. Alaska Division of Geological & Geophysical Surveys, June 2014. http://dx.doi.org/10.14509/29174.

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Sancio, Rodolfo. PR-616-164506-R01 Management of Geohazards Affecting Engineering and Construction of Pipelines. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), May 2018. http://dx.doi.org/10.55274/r0011484.

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The available literature includes numerous publications describing approaches, methods, and recommendations, for identifying, characterizing, and mitigating geohazards, as well and case histories of pipelines affected by geohazards and how their effects were mitigated. However, these publications are not comprehensive; separately provide information for identification, characterization, and mitigation; do not include all geohazards affecting pipelines; or may not have been developed specifically for pipelines. PRCI identified this gap and commissioned the development of a guidance document to succinctly incorporate geohazard management guidance into a single volume addressing i) the types of geo-hazards affecting pipelines, ii) the typical process used in practice to identify and characterize geohazards throughout the various project stages, iii) the techniques used to mitigate the geohazards, and iv) the approaches and methods recommended to project teams of owners, operators, engineers, and contractors to successfully execute projects. The guidance document is intended for a wide audience that includes technical and nontechnical managers at companies owning and operating pipelines, geoscience and engineering teams involved in studying and assessing pipeline integrity hazards, and construction staff, regulators, lenders, and other stakeholders involved in executing pipeline projects.
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Hummels, David. Toward a Geography of Trade Costs. GTAP Working Paper, January 2003. http://dx.doi.org/10.21642/gtap.wp17.

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What are the barriers that separate nations? While recent work provides intriguing clues, we have remarkably little concrete evidence as to the nature, size, and shape of barriers. This paper offers direct and indirect evidence on trade barriers, moving us toward a comprehensive geography of trade costs. There are three main contributions. One, we provide detailed data on freight rates for a number of importers. Rates vary substantially over exporters, and aggregate expenditures on freight are at the low end of the observed range. This suggests import choices are made so as to minimize transportation costs. Two, we estimate the technological relationship between freight rates and distance and use this to interpret the trade barriers equivalents of common trade barrier proxies taken from the literature. The calculation reveals implausibly large barriers. Three, we use a multi-sector model of trade to isolate channels through which trade barriers affect trade volumes. The model motivates an estimation technique that delivers direct estimates of substitution elasticities. This allows a complete characterization of the trade costs implied by trade flows and a partition of those costs into three components: explicitly measured costs (tariffs and freight), costs associated with common proxy variables, and costs that are implied but unmeasured. Acknowledgments: Thanks for the gracious provision of data go to Jon Haveman, Rob Feenstra, Azita Amjadi and the ALADI secretariat. Thanks for helpful suggestions on previous drafts go to seminar participants at the Universities of Chicago, Michigan, and Texas, Boston University, NBER and the 4th Annual EIIT Conference at Purdue University. Finally, Julia Grebelsky and Dawn Conner provided outstanding research assistance. This research was funded by a grant from the University of Chicago’s Graduate School of Business.
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Decroux, Agnes, Kassem Kalo, and Keith Swinden. PR-393-205100-R01 IRIS X-Ray CT Qualification for Flexible Pipe Inspection (Phase 1). Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), March 2021. http://dx.doi.org/10.55274/r0012068.

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There are several techniques available to inspect single wall carbon steel pipelines including; Magnetic flux leakage (MFL), ultrasonic testing (UT), Electro-Magnetic Acoustic Transducer (EMAT), Phased Array, guide wave testing (GWT), etc. However, for more complex structures such as flexible pipelines the technology available to inspect them is far more limited. PRCI commissioned a program (SPIM 2-1) under the Subsea TC (2017-2020) to evaluate all known and suspected technologies that could be used to provide a detailed subsea inspection of a flexible riser. PRCI produced four samples of flexible pipe containing pre-manufactured cracks and corrosion defects which were located in; the outer armour layer, inner armour layer, pressure vault and carcass. The samples were used for blind testing of all identified inspection technologies. On conclusion of the SPIM 2-1 program, HR-XCT was identified as the technology showing the most promise and a follow-on program (SPIM 2-2) was commissioned to further explore the capabilities. This report will show the way in which high resolution image clarity and image manipulation was extracted from the HR-XCT system when used on the PRCI flexible pipe samples. The XCT results from SPIM 2-2 will be presented to show the initial setup of the experiment and 2D and 3D high resolution sectioned images from the testing. These images clearly identify and characterize 100% of the pre-manufactured defects introduced into the samples in all layers.
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Sengupta-Gopalan, Champa, Shmuel Galili, and Rachel Amir. Improving Methionine Content in Transgenic Forage Legumes. United States Department of Agriculture, February 2001. http://dx.doi.org/10.32747/2001.7580671.bard.

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Leguminous forage crops are high in proteins but deficient in S- amino acids. It has been shown that both wool quality and milk production can be limited by the post-ruminal supply of sulfur-containing amino acids. Efforts to use conventional plant breeding and cell selection techniques to increase the S-amino acid content of alfalfa have met with little success. With the objective to increase the S-amino acid content of forage legumes, the goal of this project was to co- express the methionine rich zein genes from corn along with a gene for a key enzyme in methionine biosynthesis, aspartate kinase(AK). The zeins are seed storage proteins from corn and are groupec into four distinct classes based on their amino acid sequence homologies. The b-zein (15kd) and the 6zein (10kD and 18kD) have proportionately high levels of methionine (10%, 22% and 28%, respectively). Initial studies from our lab had shown that while the 15kD zein accumulated to high levels in vegetative tissues of transgenic tobacco the l0kD zein did not. However, co-expression of the 10kD zein with the 15kD zein genes in tobacco showed stabilization of the 10kD zein and the co-localization of the 10kD and 15kD zein proteins in unique ER derived protein bodies. AK is the key enzyme for producing carbon skeletons for all amino acids of the aspartate family including methionine. It is, however, regulated by end-product feedback inhibition. The specific objectives of this proposal were: i. to co-express the 15kD zein with the 10/18kD zein genes in alfalfa in order to enhance the level of accumulation of the 10/18kD zein; ii. to increase methionine pools by expressing a feedback insensitive AK gene in transformants co-expressing the 15kD and 10/18kD zein genes. The Israeli partners were successful in expressing the AK gene in alfalfa which resulted in an increase in free and bound threonine but not in methionine (Galili et al., 2000). Since our target was to increase methionine pools, we changed our second objective to replace the AK gene with the gene for cystathionine gamma synthase (CGS) in the co-expression studies. The first methionine specific reaction is catalyzed by CGS. An additional objective was to develop a transformation system for Berseem clover, and to introduce the appropriate gene constructs into it with the goal of improving their methionine content. Genes for the 15kD zein along with the genes for either the 10kD or 18kD zein have been introduced into the same alfalfa plant both by sexual crosses and by re-transformation. Analysis of these zein co-expressors have shown that both the IOkD and 18kD zein levels go up 5 to 10 fold when co-expressed with the 15kD zein (Bagga et al., MS in preparation). Incubation of the leaves of transgenic alfalfa co-expressing the 15kD and 10kD zein genes, in the rumen of cows have shown that the zein proteins are stable in the rumen. To increase the level of zein accumulation in transgenic alfalfa different promoters have been used to drive the zein genes in alfalfa and we have concluded that the CaMV 35S promoter is superior to the other strong leaf -specific promoters. By feeding callus tissue of alfalfa plants co-expressing the 15kD and 10kD zein genes with methionine and its precursors, we have shown that the zein levels could be significantly enhanced by increasing the methionine pools. We have now introduced the CGS gene (from Arabidopsis; kindly provided to us by Dr. Leustek), into the 15kD zein transformants and experiments are in progress to check if the expression of the CGS gene indeed increases the level of zein accumulation in alfalfa. We were not successful in developing a transformation protocol for Berseem clover.
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