18420 research outputs found
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Application of GNSS Observation Results to Determination of the Ground Deformations
No full textGlobal Navigation Satellite Systems play a principal role in understanding the movements of the Earth’s surface. Permanent observation stations record GNSS data. After collecting and processing the data provides precise information on the continuous changes of the GNSS station positions.
With the view of continuing geodynamic studies in Latvia using global data, a project of automated multifunctional optical tracking device is under construction in the Institute of Geodesy and Geoinformation of the University of Latvia. The device will be capable of SLR observations of GNSS satellites, offering a number of possibilities to improve GNSS data accuracy
Muitas dienests attīstības veicināšanai: Latvijas piemērs
No full textProblēmas, ar ko saskaras sabiedrība 21.gadsimtā ir daudz- starptautiskās tirdzniecības apjomu un sarežģītības pieaugums, pasaules ekonomikas globalizācija, nabadzības apkarošana, starptautiskais terorisms, vides aizsardzība, u.c. Šīs problēmas vistiešākā veidā skar jebkuras valsts muitas dienestus. Muita ir saskārusies ar nopietnām, bet pretrunīgām prasībām, kas tiek izvirzītas sakarā tirdzniecības paplašināšanos. No vienas puses no muitas, kā institūcijas, tiek prasīta efektīva starptautisko piegāžu ķēžu kontrole, bet no otras puses lielāki atvieglojumi likumīgai tirdzniecībai. Lai veiksmīgi risinātu šos jaunos uzdevumus tiek piedāvāti daudz drosmīgi un novatoriski risinājumi - pasaules muitas tīkls, padziļināta muitu izpratne par piegāžu ķēdēm un to vadību, kur tiktu izmantotas jaunākās tehnoloģijas, muitas partnerības stiprināšana ne tikai ar tirdzniecības pārstāvjiem, bet arī ar robežu, tiesībaizsardzības un citām valsts pārvaldes iestādēm. Kopš 2004.gada Latvijas muitas dienests saskaras ar jauniem izaicinājumiem apkalpojot Eiropas Savienības (ES) ārējo robežu un kļuvis par daļu no integrētās Eiropas ārējās robežas.
Pētījuma mērķis ir veikt Latvijas muitas dienesta pieredzes analīzi jaunāko darba un mācību metožu ieviešanā. Pētījuma rezultātā sniegti priekšlikumi par Latvijas muitas dienesta attīstības un izglītības iespēju pilnveidošanu. Rakstā izmantotas salīdzinošās analīzes, kā arī vispārpieņemtās ekonomikas zinātnes metodes
Influence of Unconditioned Spaces on the Energy Efficiency Calculation of Buildings
No full textThis study analyses the influence of assumptions of unconditioned spaces on the heat energy balance calculation model accuracy of non renovated standard residential buildings. In the Latvian legislation the accuracy demand of the heat energy balance calculation model is 10% and ≤10 kWh/m2a. The current research is performed with financial support of ERAF, project realised by University of Latvia, Nr. 2011/0003/2DP/2.1.1.1.0/10/APIA/VIAA/041
Identification of Differences of User Behavior Profiles and User Class Templates
No full textThe methods for evaluating the system effectiveness of a user behavior profile are consid
ered. For a class of users united by the same role in an information system, we consider the problem
of transition from the general to the personal user behavior adaptive profile. It is formally shown that
the profile, taking into account all the peculiarities of the behavior of a particular person, effectively
detects anomalous behavior. Experiments performed toidentify the characteristics of the profile that
are important for use in real applications are additionally realized
North-East Volatility Wind Effect in Traveling Wave Perspective. Helical Structure of Volatility wave Fourier Coefficients
No full textThis article describes new properties of North-East Volatility Wind Effect. In
current article North-East Volatility Wind Effect is analyzed from traveling wave
perspective. In current article North-East Volatility Wave is analysed via Fast Fourier Transform. Obtained Fourier coefficients are analyzed and regular helical (spiral) structure of Fourier coefficients is obtained. This research brings out idea of alternative risk measure applicable for financia time series risk analysis
Alkali Diffusion in Porous Alkali Activated Materials
No full textChemical clarification of wastewater by using high pH coagulation–flocculation processes have been investigated in laboratory
and pilot-scale experiments over the past few years. It is important that pH adjustment in the range from pH 10-11.5 in the water
treatment systems is provided continuously. Present paper reveals an idea to use novel material produced by alkali activation
technology in the passive system for stabilization of the pH in the high-pH–magnesium coagulation–flocculation wastewater
treatment systems. It is apparent that the pore solution of AAM contains a high concentration of alkali OH− and the composition
of the AAM clearly has an important effect on the diffusion of alkali from material. The AAM obtained in this research were
typically low-calcium alkali activated materials based on calcined illite clay (IC). In the low-calcium systems increased amount of
silica and higher Si/Al molar ratios promotes diffusion of alkali and geopolymerisation process of AMM is restricted by glass in
the composition and this promotes higher leaching rate of OH−. The heat treatment of specimens facilitates the leaching of OH−
ions from AAM in a prolonged period of time thus making it well suitable for use in the water treatment systems
Fractal Brownian Motion Analysis Using Continuous Wavelet Transform
No full textThis article is dedicated for Fractal Brownian process analysis using Continuous Wavelet Transform (Direct and Inverse). Wavelet Analysis of stochastic processes is very important for financial time series analysis, risk estimation and financial time series forecasting. Wavelet Analysis is very precious for scalability analysis, because of its ability to analyze the signal (process) in scaling and shifting dimensions. In current research, Fractal Brownian motion is analyzed using Direct and Inverse Continuous Wavelet Transform, wavelet coefficients probability density function is estimated, wavelet coefficients lower and upper bounds are calculated using Mexican hat mother wavelet function. At the end estimation results are illustrated
Self-Binding Composite Boards of Steam Exploded Wood Biomass. Prospects for Advancement
No full textWith account for potential use of local resources of low-quality wood biomass for purposes other than heating, a study of a possible technological solution to obtain added value wood composite products avoiding application of expensive synthetic binders the local fast-growing species of grey alder being chosen as the sample material for self-binding wood composite boards. Apart from economic considerations, conversion of biomass into products of extended usage is ecologically advantageous reducing the atmospheric carbon dioxide by the amount accumulated in the ligno-cellulosic biomass
Study on Reliability Improvement Possibilities Assuming Probabilistic Wind and Solar Generation
No full textThe paper presents approach for determination of wind and solar generation probability to back-up power supply of customers in distribution network.The developed approach is based on the analysis and usage of statistics of real generation from wind and solar resources connected to distribution network, as well as customers’ load diagrams. Proposed approach was implemented in case studies that use information on real distribution network design principles, customers’ load diagrams and statistics of distributed energy resources generation in Latvia. Case studies are based on previously performed calculations (case studies) presented by authors at PQ2012 conference in the paper “Assessment of Different Power Line Types` Life-time Costs in Distribution Network From Reliability Point of View”. Results obtained from the calculations give well-grounded base for distribution network exploiting engineers as well as individual customers when trying to find network’s optimal reliability level by replacing overhead lines by other types of power lines (as one of network reliability centered maintenance and reconstruction activities of DSO) and by using small wind power generators and photovoltaics (as activity of customers)
Managers Capabilities and Competences in Changing Environment: Empirical Study in Latvia
No full textLast decade of high economic turbulence and significant fluctuations has tested managers’ ability to adapt and apply the relevant skillset and competences to ensure success of their companies in various market conditions. The aim of research is to analyse if managerial competencies required to successfully lead a company differ in times of rapid growth or crisis and normal market conditions. Research methods such as review of the literature and organized focus groups with managers of SMEs representing various service and manufacturing industries are applied. As a result, authors developed a customized list of managerial competencies and identified individual importance of different competencies in periods of growth and crisis. Whilst research is limited to SMEs in Latvia, this is a first step in a series of studies to explore managers’ capabilities and competence models