Search results for "Wind"
showing 10 items of 846 documents
Environmental Data Processing by Clustering Methods for Energy Forecast and Planning
2011
This paper presents a statistical approach based on the k-means clustering technique to manage environmental sampled data to evaluate and to forecast of the energy deliverable by different renewable sources in a given site. In particular, wind speed and solar irradiance sampled data are studied in association to the energy capability of a wind generator and a photovoltaic (PV) plant, respectively. The proposed method allows the sub-sets of useful data, describing the energy capability of a site, to be extracted from a set of experimental observations belonging the considered site. The data collection is performed in Sicily, in the south of Italy, as case study. As far as the wind generation…
A Novel Self-organizing Neural Technique for Wind Speed Mapping
2009
Systems with high nonlinearities are, in general, very difficult to model. This is particularly true in geostatistics, where the problem of the estimation of a regionalized variable (RV) given only a small amount of measurement stations and a complex terrain surface is very challenging. This paper introduces a novel strategy, which couples the Curvilinear Component Analysis (CCA) and the Generalized Mapping Regressor (GMR). CCA, which is a nonlinear projector of a data manifold, is here used in order to find the intrinsic dimension of the data manifold, just giving an insight on the nonlinearities of the problem. This analysis drives the pre-processing of the data set used for the training …
The HisClima database: historical weather logs for automatic transcription and information extraction
2021
Knowing the weather and atmospheric conditions from the past can help weather researchers to generate models like the ones used to predict how weather conditions are likely to change as global temperatures continue to rise. Many historical weather records are available from the past registered on a systemic basis. Historical weather logs were registered in ships, when they were on the high seas, recording daily weather conditions such as: wind speed, temperature, coordinates, etc. These historical documents represent an important source of knowledge with valuable information to extract climatic information of several centuries ago. This paper presents a database for researching about the ca…
Reusability and modularity in transactional workflows
1997
Abstract Workflow management techniques have become an intensive area of research in information systems. In large scale workflow systems modularity and reusability of existing task structures with context dependent (parameterized) task execution are essential components of a successful application. In this paper we study the issues related to management of modular transactional workflows, i.e., workflows that reuse component tasks and thus avoid redundancy in design. The notion of parameterized transactional properties of workflow tasks is introduced and analyzed, and the underlying architectural issues are discussed.
Windows darbvirsmas lietotņu automatizācijas rīki
2021
Automatizētā programmatūras testēšana pēdējo 10 gadu laikā ir piedzīvojusi ļoti strauju attīstību, izplatību un izpelnijusies plašu atzinību. Tagad gandrīz katra kompānija, kas izstrādā lietotnes, automatizē vismaz daļu no saviem pastāvīgi atkārtojamajiem testiem. Līdz ar to ir strauji pieaugusi arī pieejamo automatizētās testēšanas rīku izvēle. Kā rezultātā, rodas jautājums: kurš no visiem šobrīd pieejamajiem rīkiem tirgū ir visatbilstošākais konkrētā lietotāja vai kompānijas vajadzībām. Autors savā bakalaura darbā apraksta un praktiski pielieto vairāk kā 10 gan maksas, gan bezmaksas automatizētās testēšanas rīkus un izvērtē tos pēc vairāk kā 20 dažādiem kritērijiem, kas palīdz daudz objek…
Mājas daudzfunkcionālais serveris
2015
21.gadsimta mājās nekāds retums vairs nav viens vai divi datori. Katram ģimenes loceklim ir savs, vai pat divi datori, kas kalpo ikdienas darbu veikšanai, taču to savstarpējā komunicēšana un uzturēšana nevienmēr ir tas vieglākais darbs un var radīt pavisam lielas galvas sāpes mājas iedzīvotājiem, problēmu gadījumā. Pateicoties iespējai izveidot mājas serveri, ir iespējams nodrošināt vienu kopēju vietu iemītnieku datņu glabāšanai, kas paredz iespēju koplietot izvēlētos datus starp tiem savstarpēji, kā arī izveidot automatizācijas procesu datoru uzstādīšanai, lai pēc iespējas vairāk samazinātu patērēto laiku, sistēmu konfigurēšanai un uzturēšanai. Darba gaitā tiek izveidots multifunkcionāls m…
Mājas tīkla un servera izveide ar Windows Server 2016
2017
Kvalifikācijas darbā apskatītas mājsaimniecības privātā tīkla funkcionalitātes nepilnības un to risinājumu iespējas izmantojot izvēlēto sistēmu – Windows Server 2016. Darba mērķis ir uzlabot esošo LAN tīklu drošības un funkcionalitātes aspektā. Darba kontekstā risinātās problēmas ir aktuāls jautājums mūsdienu mājsaimniecībās, kur privāto tīklu veido vairāk kā 2-3 darbstacijas, mobilās iekārtas, tiek izmantota bezvadu piekļuve internetam un lietotāju starpā ir bērni. Darba teorētiskajā daļā veikta esošā mājas tīkla iekārtu un sistēmu izpēte, lai nodrošinātu piemērotākā risinājuma ieviešanu. Kā arī definēti darba gaitā izpildāmie uzdevumi, vadoties pēc lietotāju stāstiem. Darba praktiskajā da…
Daytime sensible heat flux estimation over heterogeneous surfaces using multitemporal land-surface temperature observations
2016
Equations based on surface renewal (SR) analysis to estimate the sensible heat flux (H) require as input the mean ramp amplitude and period observed in the ramp-like pattern of the air temperature measured at high frequency. A SR-based method to estimate sensible heat flux (HSR-LST) requiring only low-frequency measurements of the air temperature, horizontal mean wind speed, and land-surface temperature as input was derived and tested under unstable conditions over a heterogeneous canopy (olive grove). HSR-LST assumes that the mean ramp amplitude can be inferred from the difference between land-surface temperature and mean air temperature through a linear relationship and that the ramp freq…
Recent advances on ionic liquid uses in separation techniques
2018
International audience; The molten organic salts with melting point below 100°C, commonly called ionic liquids (ILs) have found numerous uses in separation sciences due to their exceptional properties as non molecular solvents, namely, a negligible vapor pressure, a high thermal stability, and unique solvating properties due to polarity and their ionic character of molten salts. Other properties, such as viscosity, boiling point, water solubility, and electrochemical window, are adjustable playing with which anion is associated with which cation. This review focuses on recent development of the uses of ILs in separation techniques actualizing our 2008 article (same authors, J. Chromatogr. A…
FLOW PATTERN AROUND THE RIGID CEPHALIC SHIELD OF THE DEVONIAN AGNATHANERRIVASPIS WAYNENSIS(PTERASPIDIFORMES: HETEROSTRACI)
2008
Palaeozoic armoured agnathans (or ostraco- derms) are characterised by having an external, bone shield enclosing the anterior part of their bodies, which demon- strate great diversity of both forms and sizes. The functional significance of these cephalic shields remains unclear (they may have been a functional analogue of the vertebral col- umn, or merely afforded protection). Here we assess the importance of the cephalic shield in terms of locomotion. In order to do this, we have studied flow patterns of the Devo- nian heterostracan Errivaspis waynensis (White, 1935), using an anatomically correct model of E. waynensis positioned at different pitching angles. The fluid flow was visualised …