Search results for "ETL"
showing 10 items of 431 documents
ETL procesu automatizācija datu noliktavā
2018
Viens no liekākajiem, sarežģītākajiem un laikietilpīgākajiem uzdevumiem datu noliktavā ir ETL procesu izveide, jo ETL tieši ietekmē datu kvalitāti. Viens no veidiem, kā samazināt laiku un resursus, kas tiek iztērēti ETL ir izmantot automatizāciju, kas varētu samazināt cilvēcisko kļūdu rašanos un uzlabot kopējo procesu. Bakalaura darbā “ETL procesu automatizācija datu noliktavā” autore sniedz ieskatu ETL procesu nozīmē, izveides galvenajos soļos un to automatizācijas ierobežojumiem un nepieciešamību datu noliktavā. Darbā ir veikts pētījums, kur autore izveidoja automatizētus ETL procesus izveidotajai datu noliktavai, nodrošinot, regulāru izpildi un datu kvalitāti. Pētījums veikts ar atvērtā …
Datu transformāciju iespējas Oracle vidē
2016
Datu transformācijas ir laikietilpīgs process regulārajās ielādēs. Tām jānotiek ātri, noteiktās laika robežās. Uzņēmuma datu noliktavā tiek izstrādāts viens problēmas risinājums, nevis vairāki, izvēloties ātrdarbīgāko, tāpēc autors apskata vairākas transformāciju alternatīvas 4 problēmu risināšanai: 1. Hierarhisko datu vairāku līmeņu attēlošanai rindā; 2. Hierarhisko slēguma datu attēlošana rindā; 3. Divu vēstures tabulu apvienošana ar pārklājošiem periodiem 4. Vēstures tabulas vispārināšana, pārrēķinot sākuma un beigu datumus. Praktiskajā daļā katrai no problēmām tika atrasti/izstrādāti, aprakstīti un salīdzināti 2 – 3 risinājumi, starp kuriem noteikts ātrākais izpildes laiks attiecīgās pr…
ECOHYDROLOGICAL MODELLING IN MEDITERRANEAN AREAS AND WETLANDS
2010
La seguente dissertazione verte sul campo di ricerca noto come Ecoidrologia. Sebbene tale scienza, che studia le mutue interazioni fra ciclo idrologico e gli ecosistemi naturali, sia stata recentemente oggetto di svariati studi, alcuni dei suoi numerosi aspetti rimangono tuttavia ancora alquanto inesplorati. L’obiettivo principale della presente tesi è quello di rivisitare la letteratura scientifica esistente sull’argomento, cercando di adattare concetti e modelli sviluppati per certi ecosistemi anche alle peculiarità di altri ambienti meno studiati, come quelli aridi e semiaridi tipici della zona Mediterranea o le cosiddette “wetlands”, zone umide e paludose. In particolare, viene approfon…
Monitoring Subaquatic Vegetation Using Sentinel-2 Imagery in Gallocanta Lake (Aragón, Spain)
2022
Remote sensing allows the study of aquatic vegetation cover in shallow lakes from the different spectral responses of the water as the vegetation grows from the bottom toward the surface. In the case of Gallocanta Lake, its seasonality and shallow depth (less than 2 m) allow us to appreciate the variations in the aquatic vegetation with the apparent color. Six common vegetation indices were tested, and the one with the best response was the so-called NDI45, which uses the normalized ratio between the far red (705 nm) and red (665 nm) bands. Our aims are to show the variations in the surface area covered by vegetation at the bottom of the lagoon, its growth and disappearance when drying occu…
Do female leaf beetles Galerucella nymphaeae choose their mates and does it matter?
1998
The role of active female choice in sexual selection is frequently difficult to ascertain, and this is particularly the case for many insect species. Also, it is uncertain whether choosing between males would affect offspring viability. We designed an experiment to investigate the presence of female choice in a Coleoptera species (Galerucella nymphaeae). We also estimated whether mate choice would have any effect on offspring performance. Females were first placed with two males in a test arena to see which of the males copulated with the virgin female, and how quickly. Subsequently the loser male was offered a new virgin female to test for any change in latency time until mating. The two-m…
On the presence of the alien exotic sap beetle Phenolia (Lasiodites) picta (Macleay, 1825) (Coleoptera Nitidulidae) in Italy
2020
The exotic sap beetle Phenolia (Lasiodites) picta (W.S. Macleay, 1825) (Coleoptera Nitidulidae) is an alien species recently recorded in Europe (Spain, France, and Greece), and Turkey. For Italy, only a single record of P. cf. picta is reported from Sicily. In this paper, we studied this specimen confirming the presence of P. picta in Italy.
Species Composition and Structure of Beetle Associations in Caves of the Częstochowa Upland, Poland
2023
This paper presents the study’s results on beetles (Insecta: Coleoptera) inhabiting caves in the Częstochowa Upland, southern Poland. During two years of research, 2084 specimens, representing 105 species from 19 beetle families, were collected. The obtained results indicate that many beetle species choose to inhabit caves despite lacking specific adaptations for living in such environments. The cave entrance zone is the most attractive place for surface species to inhabit because its climatic conditions are more stable than outside the cave, some sunlight is present, and the availability of organic matter is high. In the deeper parts of the studied caves, the number of occurring species ra…
Environmental Benefit of Improving Wastewater Quality: A Shadow Prices Approach for Sensitive Areas
2018
The use of effluents from wastewater treatment plants (WWTPs) as a non-conventional source of water for wetlands in arid and semi-arid regions is becoming the most-often sought solution for maintaining water flow in sensitive wetlands there. However, the managing effluent quality should be a requirement because excess nutrients (mainly nitrogen and phosphorus) can generate eutrophication problems in wetlands. In the Mediterranean area in general, wetlands are strongly vulnerable to eutrophication, which is why they are classified as sensitive areas. Our study uses a data set from 24 WWTPs, effluents of which are discharged to wetlands in the coast of Community of Valencia. We use the shado…
Electric conduction in solids: a pedagogical approach supported by laboratory measurements and computer modelling environments
2008
In this paper we present a pedagogic approach aimed at modeling electric conduction in semiconductors, built by using NetLogo, a programmable modeling environment for building and exploring multi‐agent systems. ‘Virtual experiments’ are implemented to confront predictions of different microscopic models with real measurements of electric properties of matter, such as resistivity. The relations between these electric properties and other physical variables, like temperature, are, then, analyzed.
Beetles (Coleoptera) caught with pheromones of Gnathotrichus retusus and G. sulcatus (Col., Scolytidae) in southern Finland
2001
The ambrosia beetle Gnathotrichus materiarius, which originally came from North America, was discovered in southern Finland in 1996. In 1997, using Norwegian drainpipe traps baited with pheromones of Gnathotrichus retusus and G. sulcatus, we collected beetles in the region where the first specimen had been caught in order to determine whether this potential pest species had become established in the area. Samples from a total of 16 traps included 79 species of beetles and 719 individuals, but no specimens of G. materiarius. The most abundant species in the samples were the ambrosia beetles Xyleborus dispar and Trypodendron lineatum. Several predators and other associates of bark beetles wer…