18420 research outputs found
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Conceptual Framework of Integrated Technologies for Remote Sensing and Monitoring of Natural-Technological Systems
No full textThis paper describes an ongoing development of integrated technological framework for remote sensing and monitoring of complex systems containing natural, technological and social elements. The proposed framework provides computationally efficient and user-centered geospatial monitoring, analysis and modelling features based on heterogeneous information received from space and ground-based data sources
Heisterbahas Cēzarija vēstījums par Kaupo uzklausīto grēksūdzi un Livonijas recepcija 13.gadsimta Eiropas intelektuālajā tradīcijā
No full text13.gadsimta sākums ir viduslaiku Eiropas civilizācijas pilnīgas izveides laiks, kas cieši saistīts ar Livonijas tēla iekļaušanu Eiropas literārajā telpā. Vienlaikus ar Romas baznīcas koordinēto reliģisko priekšstatu transplantāciju Baltijā notiek arī šo priekšstatu noformēšanās Eiropā kopumā, izkristalizējoties tādiem jēdzieniem kā "elle", "paradīze", "Dieva brīnums", "eņģeļi", "dēmoni" un "šķīstītava" (purgatorijs), kas ilgus gadsimtus noteica iedzīvotāju pasaules uzskatu un mentalitāti. Livonijai sakarā ar ilgajām pagānisma tradīcijām, no vienas puses, un ārkārtīgi ātro integrāciju viduslaiku kristietībā, no otras puses, šajā procesā bija izcila vieta
Involvement by Involved Model for Nongovernmental Organisation Development under Innovation Conditions
No full textThe research is targeted to develop a model that could attract more ideas and approaches to the nongovernmental organisation by involving its target group in the realisation of the projects. The main resource for involving the new participants are already involved members from the target groups. Generally the model increase organisation’s access to the human resources not only for reducing the workload of the permanent staff, but also for attracting additional informational and intellectual resource. The main challenges of using the model is related with an additional load one the quality assurance system of the organisation, as well as the instability of the team; these challenges can deploy more effect on larger organisations
Simulating the Influence of the Height of HPP Dams on the Environmental Conditions in Small River Virvyte
No full textn natural floodplains, the grassed areas usually entrap fine suspended sediments (wash products rich in nutrients) of the floodwater, thus contributing to the process of self-purification. However, hydroelectric power plants (HPPs), built with the purpose of employing the renewable energy, can worsen this process, it occurs if they pond the floodplains and decrease these grassed areas. In the present paper, the sediment deposition in the floodplains with existing weir heights is investigated. The mathematical-hydraulic model is used for it. The 12 km length interval of the river Virvyte, having three ponds was investigated. The average volume of sedimentation in this region is 500-2000 t/year, i.e. quite large. In the investigated region of the river Virvyte, the sediment deposition decreased by about 50%, due to the impact of a too high dam (H=5.5 m) of the Kapėnai HPP. © 2013 Copyright Vilnius Gediminas Technical University (VGTU) Press
Radiation Chemistry of Salicylic and Methyl Substituted Salicylic Acids: Models for the Radiation Chemistry of Pharmaceutical Compounds
No full textSalicylic acid and its derivatives are components of many medications and moieties found in numerous pharmaceutical compounds. They have been used as models for various pharmaceutical compounds in pharmacological studies, for the treatment of pharmaceuticals and personal care products (PPCPs), and, reactions with natural organic matter (NOM). In this study, the radiation chemistry of benzoic acid, salicylic acid and four methyl substituted salicylic acids (MSA) is reported. The absolute bimolecular reaction rate constants for hydroxyl radical reaction with benzoic and salicylic acids as well as 3-methyl-, 4-methyl-, 5-methyl-, and 6-methyl-salicylic acid were determined (5.86±0.54)×109, (1.07±0.07)×1010, (7.48±0.17)×109, (7.31±0.29)×109, (5.47±0.25)×109, (6.94±0.10)×109 (M−1 s−1), respectively. The hydrated electron reaction rate constants were measured (3.02±0.10)×109, (8.98±0.27)×109, (5.39±0.21)×109, (4.33±0.17)×109, (4.72±0.15)×109, (1.42±0.02)×109 (M−1 s−1), respectively. The transient absorption spectra for the six model compounds were examined and their role as model compounds for the radiation chemistry of pharmaceuticals investigated
Chapter 8: Fiber Bragg Grating Technology for New Generation Optical Access Systems
No full textApplications of both short-and long-period fiber gratings are very diverse, especially
the ones related to the optical communications and the optical fiber sensing. In optical
communications different tasks such as wavelength selective filtering, add/drop
multiplexing and all-optical switching have been performed. Interestingly, optical
fiber sensing has unique advantages such as immunity to electromagnetic radiation,
high sensitivity, cost-effective relation, etc. And it is widely used to measure stress,
temperature, pressure or chemical parameters, among others physical variables,
giving in many cases unrivaled resolution capabilities. In this book the reader will find a collection of chapters written by different experts
around the world, covering the broad field of fiber gratings. The main goal of this
book is to give an updated overview of the current research trends in the rapidly
evolving field of fiber gratings
Spectrum Usage in Mobile Broadband Communication Systems
No full textThe increased demand of mobile broadband consumers on services in the mobile environment with high data rate and technologically developed mobile broadband communication systems will require more spectrum to be available in the future. The new technologies as well as the existing services require frequencies for their development. The authors investigate the available and potential future mobile terrestrial frequency bands - worldwide and in Europe. An insight into the spectrum management is provided, with radio access technologies, methods for more efficient use of mobile frequency bands and frequency cross-border coordination also addressed. It is stressed that the radio frequency spectrum is a limited national resource that will become increasingly precious in the future
Assessment of Roadside Particulate Emission Mitigation Possibilities
No full textThe improvement of air quality is now an issue for
all developed countries. In the European Union transportation is
the main source of NOx pollution and the second most significant
PM10 and PM2, 5 emission sources. The focus of the research is
transportation PM10 emissions. The paper introduces a model of
system dynamics for analysis of road transportation PM10
emissions. The developed model is then used to compare PM10
emissions in 4 cases, one of which is the baseline, while in the
other 3 a variety of road transport emission reduction methods
are implemented. The simulation results have shown that the
highest daily PM10 emission reductions can be achieved by
combining technological and administrative methods.
Administrative methods (rush-hour driving tax and heavy vehicle
traffic restrictions) turned out to be the most effective
Energetic Refurbishment of Historic Brick Buildings: Problems and Opportunities
No full textBuilding standards for energy effectiveness are
increasing constantly and the market follows these changes by
constructing new buildings in accordance with standards and
refurbishment of the existing housing stock. Comprehensive
trends in European construction market show tremendous
increase in building retrofit works. It can be predicted that after
the end of this decade, more than half of the construction works
in European cities will be taking place in existing buildings,
pushing the construction of new buildings to a less important
role. Such a growth in building refurbishment works is creating a
demand for suitable materials, retrofitting techniques and
research. The differences between refurbishment of new-build
projects and historical or valuable buildings are insufficiently
recognized – mostly the buildings without further cultural
preservation requirements are studied. This article covers the
theme of refurbishment measures in historical buildings – the
specific measures like inside insulation which are allowed due to
the valuable façade or other heritage preservation requirements.
An overview of other innovative methods for energy saving in
existing buildings and their potential is given
Improvement of Solar PV Efficiency. Potential Materials for Organic Photovoltaic Cells
No full textOrganic photovoltaic (OPV) cells are considered as
a viable alternative to those energy sources currently in use. In
this work three derivatives of original N,N’-
dimetilaminobenziliden-1,3-indandione (DMABI) material are
presented as potential materials for OPV. The photoconductivity
threshold energy was evaluated from the perspective of spectral
dependence of photoconductivity quantum efficiency, and the
optical energy gap was defined to determine the optical
absorption spectra. The absorption spectra of derivatives are
blue shifted compared to original DMABI. Use of these
derivatives in multilayer solar cells with original DMABI makes
it possible to broaden the spectral response range of OPV