48 research outputs found
CONSIDERATIONS CONCERNING THE AUTOMATION OF PROTECTED SPACES
In the last period there is an intensification of the researches oriented towards the automation of the specific activities of the horticultural production in protected spaces. The greenhouses offer a shelter in which a microclimate suitable for plants is maintained, which is obtained by regulating / adjusting the heat and the amount of light coming from the sun, by means of actuation systems (actuators-technical devices that generate an action to reach a specific objective). The paper presents a brief communication on the main drive systems used in greenhouses: ventilation and cooling systems; heating systems; irrigation systems, whose drive systems are mainly composed of electrical devices, especially electric motors or pump
A REAL-TIME MONITORING APPLICATION OF ENVIRONMENTAL CONDITIONS IN PROTECTED AREAS
With the development of technology, the greenhouse sector is constantly expanding, which is advantageous in terms of material economy, cost reduction, improved lighting efficiency and cultivation, but at the same time requires the implementation of a large number of sensor nodes to ensure coverage of environmental monitoring. The paper presents a real-time monitoring application of environmental conditions in a greenhouse, which includes sensors for monitoring temperature, relative humidity; CO2 concentration; soil temperature (at 3 depths: ground level, 10, 20 cm)
STUDY ON THE CONVERSION OF A CONVENTIONAL TRACTOR INTO AN ELECTRIC TRACTOR
The paper presents the study on how a classic tractor with internal combustion engine can be modified so that it is powered by a battery-powered electric motor. The article presents equipment and components with which a tractor can be modified so that it can run on electricity. In general, an electric tractor consists of the chassis from which the heat engine, electric motor, battery, control and configuration equipment, software used and communication equipment, of the electronic systems on board the tractor are removed
GENERAL ASPECTS REGARDING THE GROWTH FRESHWATER FISH IN CUBES, AN ALTERNATIVE FOR AQUACULTURE IN ROMANIA
Due to the increased consumption of fish, as an alternative to achieving healthy population nutrition, the development of European aquaculture also shows an increasing trend. At present, freshwater culture is about 42% of total European fish production. Valuable species, from an economic point of view, can be reared in intensive systems in cages on running waters or ponds, combined with less valuable species. There are also new species that are gradually becoming increasingly important for the fish industry in Europe. Freshwater aquaculture in Romania is based on rainbow trout and carp which are still predominant species, but there is significant demand for valuable fish species [11,12,16]. Â
Harmonic Analysis of Boolean Networks: Determinative Power and Perturbations
Consider a large Boolean network with a feed forward structure. Given a
probability distribution on the inputs, can one find, possibly small,
collections of input nodes that determine the states of most other nodes in the
network? To answer this question, a notion that quantifies the determinative
power of an input over the states of the nodes in the network is needed. We
argue that the mutual information (MI) between a given subset of the inputs X =
{X_1, ..., X_n} of some node i and its associated function f_i(X) quantifies
the determinative power of this set of inputs over node i. We compare the
determinative power of a set of inputs to the sensitivity to perturbations to
these inputs, and find that, maybe surprisingly, an input that has large
sensitivity to perturbations does not necessarily have large determinative
power. However, for unate functions, which play an important role in genetic
regulatory networks, we find a direct relation between MI and sensitivity to
perturbations. As an application of our results, we analyze the large-scale
regulatory network of Escherichia coli. We identify the most determinative
nodes and show that a small subset of those reduces the overall uncertainty of
the network state significantly. Furthermore, the network is found to be
tolerant to perturbations of its inputs
CONSIDERATIONS ON PLANTS AND TECHNIQUES FOR OBTAINING BIO INSECTICIDES USED IN ORGANIC FARMING
The paper presents a few aspects regarding the development of organic agriculture in our country and abroad in the last years, the plants containing substances that can be used as organic insecticide, respectively the techniques and procedures used for obtaining these insecticides
TESTING THE RESISTANCE STRUCTURES OF TRACTORS AND AGRICULTURAL MACHINERY UNDER SIMULATED AND ACCELERATED REGIME
The need for an increased quality of products, the reduction of the production entry time and the restrictions imposed by the service period of products are the essential reasons which impose the necessity of using the simulated and accelerated regime tests. An accelerated test is necessary to produce the same content of wear deterioration as that one supported by the product (machine, gear, subsystem or component) on its lifetime in normal functioning conditions. Although a test in accelerated regime doesn`t have to produce big loads, unrealistic, which could alter the defecting mechanism? The paper presents the principal methods of test acceleration and exemplifies the test in accelerated and simulated regime by a test of endurance effectuated on the structure of a two plough body, on the Hydropulse stand inside of Testing Department from INMA Bucharest. Also, the paper present photos that were taken during the years from tests in simulated and accelerated regime, on the Hydropulse stand, of different machines and agricultural gears
CONSIDERATIONS REGARDING THE HARVESTING TECHNOLOGIES OF JERUSALEM ARTICHOKE
Jerusalem artichoke (Helianthus tuberosusL.) is not cultivated on the large surface that cereals, vegetables or potatoes so mechanizes technologies are not very often encountered. In this paper are presented few technologies used on the country where this culture occupied large surface and not only
Empirical analysis and modeling of Argos Doppler location errors in Romania
Background Advances in wildlife tracking technology have allowed researchers to understand the spatial ecology of many terrestrial and aquatic animal species. Argos Doppler is a technology that is widely used for wildlife tracking owing to the small size and low weight of the Argos transmitters. This allows them to be fitted to small-bodied species. The longer lifespan of the Argos units in comparison to units outfitted with miniaturized global positioning system (GPS) technology has also recommended their use. In practice, large Argos location errors often occur due to communication conditions such as transmitter settings, local environment, and the behavior of the tracked individual. Methods Considering the geographic specificity of errors and the lack of benchmark studies in Eastern Europe, the research objectives were: (1) to evaluate the accuracy of Argos Doppler technology under various environmental conditions in Romania, (2) to investigate the effectiveness of straightforward destructive filters for improving Argos Doppler data quality, and (3) to provide guidelines for processing Argos Doppler wildlife monitoring data. The errors associated with Argos locations in four geographic locations in Romania were assessed during static, low-speed and high-speed tests. The effectiveness of the Douglas Argos distance angle filter algorithm was then evaluated to ascertain its effect on the minimization of localization errors. Results Argos locations received in the tests had larger associated horizontal errors than those indicated by the operator of the Argos system, including under ideal reception conditions. Positional errors were similar to those obtained in other studies outside of Europe. The errors were anisotropic, with larger longitudinal errors for the vast majority of the data. Errors were mostly related to speed of the Argos transmitter at the time of reception, but other factors such as topographical conditions and orientation of antenna at the time of the transmission also contributed to receiving low-quality data. The Douglas Argos filter successfully excluded the largest errors while retaining a large amount of data when the threshold was set to the local scale (two km). Discussion Filter selection requires knowledge about the movement patterns and behavior of the species of interest, and the parametrization of the selected filter typically requires a trial and error approach. Selecting the proper filter reduces the errors while retaining a large amount of data. However, the post-processed data typically includes large positional errors; thus, we recommend incorporating Argos error metrics (e.g., error ellipse) or use complex modeling approaches when working with filtered data