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Open access

H. S. Ginwal, Pradip Kumar, V. K. Sharma and A. K. Mandal

Abstract

Results of a provenance trial of Eucalyptus camaldulensis Dehnh. laid out in 2001 at Seothi (30° N Lat., 76° E Long. and 250 m altitude) Haryana, a semi-arid region of India are reported and discussed. Six seed sources from Australia viz. Laura River, Emu Creek, Degrey River, Wiluna, Kennedy River, Morehead River were evaluated from nursery stage (3 months) to field performance (2 year). Two sources viz. E.tereticornis (Helenvele, Qld) and FRI-4 a local seed source were used as control (check material). Significant differences between the seed sources at nursery stage were observed for collar diameter (P < 0.05) and number of leaves (P < 0.01). At age 2 years, significant differences between the seed sources (P < 0.05) were observed for height and field survival. The two seed sources viz. Emu Creek Petford, QLD and Laura river, QLD ranked first and second for height and survival at this age. Results indicate that genetic differences exist between the sources of E. camaldulensis. None of the traits assessed (viz. height, collar diameter, number of leaves, number of branches and survival) was found to correlate with any of the geographical coordinates of the site (latitude, longitude and altitude). There were fair differences between phenotypic and genotypic coefficient of variability. Heritability values were fairly high for height and clear bole length in comparison to collar diameter, number of branches and survival. The relative performance of these provenances was fairly consistent throughout the period of observation. The two sources viz. Laura river, QLD and Emu Creek Petford, QLD are recommended for potential source for plantation programme under semi-arid conditions.

Open access

Mihaela Bratu Simionescu

Abstract

The GDP forecasting presents a particularity resulted from the fact that this macroeconomic indicator can be analyzed in its quality of aggregate. Therefore, the GDP can be predicted directly using an econometric model with lagged variables represented by the aggregate component. On the other hand, the same GDP can be predicted by aggregating the forecasts of its components. The aim of this study is to find out which strategy generates the most accurate one-step-ahead prediction and if combined forecasts can be a solution of improving the forecasts accuracy. Starting from the GDP oneyear- ahead predictions made for 2009-2011 using the two strategies, measures of accuracy were calculated and the directly predicted GDP are better than those based on aggregating the components using constant and variable weights. Combined forecasts did not improve the accuracy of the predictions based on the mentioned strategies. This research is a good proof for putting the basis of considering the variables aggregation as an important source of uncertainty in forecasting.

Open access

I.-K. Fontara, F. Wuttke, S. Parvanova and P. Dineva

for a Buried Source. J. Geophys. Res., 44 (1978), 603-612. [12] Wuttke, F. Beitrag zur Standortidentifzierung mit Oberfachenwellen, PhD thesis, Germany, Weimar, Bauhaus Universitat, 2005. [13] Bouchon, M. A Simple Method to Calculate Green’s Functions for Elastic Layered Media. Bull. Seism. Soc. Am., 71 (1981), 959-971. [14] Moczo, P. Finite-difference Technique for SH Waves in 2-D Media using Irregular Grids: Application to the Seismic Response Problem. Geophys.J. Int., 99 (1989), 321-329. [15] Gatmiri

Open access

Dariusz Mikielewicz and Jarosław Mikielewicz

Utilisation of bleed steam heat to increase the upper heat source temperature in low-temperature ORC

In the paper presented is a novel concept to utilize the heat from the turbine bleed to improve the quality of working fluid vapour in the bottoming organic Rankine cycle (ORC). That is a completely novel solution in the literature, which contributes to the increase of ORC efficiency and the overall efficiency of the combined system of the power plant and ORC plant. Calculations have been accomplished for the case when available is a flow rate of low enthalpy hot water at a temperature of 90 °C, which is used for preliminary heating of the working fluid. That hot water is obtained as a result of conversion of exhaust gases in the power plant to the energy of hot water. Then the working fluid is further heated by the bleed steam to reach 120 °C. Such vapour is subsequently directed to the turbine. In the paper 5 possible working fluids were examined, namely R134a, MM, MDM, toluene and ethanol. Only under conditions of 120 °C/40 °C the silicone oil MM showed the best performance, in all other cases the ethanol proved to be best performing fluid of all. Results are compared with the "stand alone" ORC module showing its superiority.

Open access

I. Wasiak and Z. Hanzelka

Integration of distributed energy sources with electrical power grid

The changes that have been taking place recently in the power sector, lead to an increasing share of distributed generation (DG) in the electric power production. Many different energy sources can be distinguished in this area and majority of them incorporate power electronic electrical energy converters interfacing with a power system. Connection of a large number of distributed energy sources (DES) changes the power system work conditions both in positive and negative sense. On the one hand, they emit disturbances to electric power network and on the other hand, they can be effective means of the compensation of such disturbances and also can be used to improve the quality of power delivery. Their additional capabilities are performed by power electronic converters.

Development of a modular universal interconnection architecture of these converters with standard functions for power conversion, power conditioning and quality, protection, controls, communications, ancillary services, and metering is the cornerstone of streamlined DG interconnection. Similarly, developing standard certification and testing procedures for the interconnection of DG converters, and then deploying and field testing many of the recently commercialised interconnection devices is a needed step in this process.

The main goal of this paper is to present the possibilities of application of the power electronic converters coupling DESs with supply networks to perform ancillary services resulting from supply network characteristics.

In the first part the interaction between DESs and networks is described and quantified. Then ancillary services are defined, as the new tasks that designers of converter can/should undertake as well as the standardization gap with respect to the converters that perform ancillary services. For the purposes of this paper the converter is considered to be a black box connected to the power system. The paper concerns DESs connected to distribution networks.

Open access

Jakub Szałatkiewicz, Roman Szewczyk, Mateusz Kalinowski, Juhani Kataja, Peter Råback, Juha Ruokolainen and Maciej Kachniarz

Abstract

Microwave devices are widely used in the industry and in the specialized laboratory analyses. Development of such devices requires the possibility of modeling of microwave energy distribution in the specific resonant chambers. Until now, such modeling was possible only with the use of commercial software or was limited to specific cases. The paper presents an open-source module for ELMER software for solving timeharmonic Maxwell’s equations, allowing modeling of microwave waveguide lines. Three test cases of different resonant chambers are investigated at 2.45 GHz frequency. Modeling results obtained from the open-source ELMER Vectorial Helmholtz module show that the application of this software can be effective in R&D works, enabling high-tech small and medium enterprises involvement in advanced microwave technology.

Open access

Open Source Archaeology

Ethics and Practice

Open access

Bonaventure Chukwujindu Echezona, Chinedu Felix Amuji and Simon Eze

Abstract

The relative susceptibility of different accessions of Bambara groundnut (Vigna subterranean L. Verdc) to Callosobruchus maculatus (F.) was assessed in a laboratory trial in Nigeria. Treatments were comprised factorial combinations of four grain sources from Nigeria (Enugu, Anambra, Benue and Kogi state) and three predominantly contrasting seed coat colours (black, brown, and milky-colour) laid out in a completely randomized design (CRD). There were four replications of each treatment. Egg depositions by adult C. maculatus were affected by grain sources such that ovipositions on those sourced from the state of Anambra were significantly (p < 0.05) higher than those from other sources. Similarly, black coloured grains harboured more insects and eggs compared to other seed coat colours. Accesssions collected from Benue and/or those with a milky-coloured seed coat showed some levels of oviposition deterrence. However, the interaction of grain source and seed coat colour was not significant based on oviposition, adult emergence, and mortality counts. Grain sources and seed coat colour were, therefore, important traits to be considered while selecting ideotypes for resistance to C. maculatus

Open access

Irina Dubravina, Igor Vasilenko, Irina Chepinoga and Sergey Gorlov

растений]. Branch Krymsk experimental breeding station of the All-Russian Re¬search Institute of Plant Industry, Krymsk. 46 pp. Eremin, G. V., Dubravina, I. V., Kovalenko, N. N., Gasanova, T. A. (2015). Preliminary Breeding of Fruit Crops (Еремин, Г. В., Дубравина, И. В., Коваленко, Н. Н., Гасанова, Т. А. Предварилельная селекция плодовых культур]. Eremin, G. V. (Ed.). KubSAU, Krasnodar. 335 pp. Eremin, G. V. (2014). Genetic analysis of source material for using it in plum breeding in the South of Russia [Еремин, Г. В. Генетический анализ

Open access

Artūrs Bartusevičs, Andrejs Lesovskis and Viktorija Ponomarenko

Abstract

Large software development projects with high levels of agility require several IT operations: software configuration management, bug tracking management, making software builds and deployments. Due to high agility in projects, the starting phases are very chaotic and sometimes in a few days customer is willing to get the first release of software. It means that all IT operations should be automated as soon as possible. The study presents a model-driven approach for automation of IT operations through the reuse of the existing source code. In addition, it presents a method for the development of library of reusable source code. The paper contains a brief description of the model-driven approach, library of source code and meta-models developed for a new methodology. The paper ends with the results of the practical experiments and conclusions on how this approach could be improved in the future.