Wiley InterScience

A number of studies have indicated that the tension-stiffening law is an important input parameter in a numerical analysis of serviceability (deformations and cracking) problems of reinforced concrete (RC) structures. The stochastic nature of concrete cracking, which results in a large scatter of experimental results, renders the constitutive modeling a very difficult task. Even data obtained from short-term tests are to some degree uncertain due to time-dependent processes occurring in concrete, such as shrinkage and creep relaxation. This article provides statistical analysis tools that can be readily applied to engineering practice. Stochastic principles are applied to modeling of tension-stiffening for the purpose of predicting not only the average deformation response of RC elements, but also bounds of these predictions that are of vital importance for practical problems. Unlike common practice, shrinkage of concrete is taken into account in the short-term numerical simulation.

Over the last decade, pavement instrumentation has become an important tool for monitoring the performance of pavement structures and materials under real climatic and traffic conditions. Stress, strain transducers, loop profilers, temperature, and moisture sensors could be reasonably used for sophisticated analysis of pavement performance. Commonly, such research projects involve only few pavement structures under accelerated loading tests. The unique experimental road section was constructed in 2007 in Lithuania. It consists of 27 different flexible pavement structures and all necessary electronic sensors. This road is affected by real climatic conditions and high-intensity heavy vehicle traffic. The aim of such research is to continuously monitor performance of different pavement structures and to elaborate on the most suitable and economically effective pavement structures.

The design of infrastructure systems for "accidental" situations, i.e., abnormal service conditions, may include a comparison of alternative design solutions of system components. These solutions are compared by means of applying a universal methodology known as a multiattribute selection (MAS). The alternative designs are described by a number of attributes that characterize each of them. Failure probability and quantitative measure of the risk are used as safety-related attributes of the alternative designs. This article shows how to carry out the MAS in the presence of epistemic uncertainties in safety-related attributes. Distributions of epistemic uncertainties are specified by means of methods used for quantitative risk assessment. The MAS is carried out as a propagation of these uncertainties. The Monte Carlo simulation is used to propagate uncertainties through the algorithm of MAS. The approach proposed in this article is illustrated by two examples, which consider alternative designs of a protective barrier and alternative sprinkler systems.

Comprehensive investigation of optical and electrical characteristics of nitride-based (InGaN) light emitting diodes (LEDs), and comparison of the results with those for phosphide-based (AlInGaP) are presented. The main attention was pointed to investigation of the optical and electrical fluctuations and their correlation. It is shown that correlation factor between optical and electrical fluctuations is very sensitive to device defectiveness.

Bioelectrodes employing the conversion of N-substituted phenothiazine/hexacyanoferrate(II) and N-substituted phenoxazine/hexacyanoferrate(II) that act as synergistic substrates were built using graphite electrode and recombinant laccase. The response of the bioelectrodes to low reactive substrate (hexacyanoferrate(II)) increases 2.9-97 times in presence of high reactive phenothiazine or phenoxazine mediator. The sensitivity of the bioelectrodes reaches 0.5-14.3 A/Mcm2. To background a scheme of bioelectrodes action the kinetics of laccase-catalyzed synergistic substrates oxidation was investigated in homogenous solution. A satisfactory agreement of experimentally determined rate constants and calculated using parameters of bioelectrocatalytical system confirms the scheme of bioelectrodes action.

The formation of the complexes between Cibacron blue F3G-A and two therapeutic proteins, recombinant human interferon-2b and recombinant human growth hormone, was investigated. The method of time-resolved limited proteolysis coupled with MALDI-TOF mass spectrometry was used. The analysis of peptide maps revealed that A17HR19 and L20HQLAFDTYQEFEEAYIPK38 of hGH, and R14TLMLLAQMR23 and D33RHDFGFPQEEFGNQFQK50 of hIFN-2b, exhibit affinity to Cibacron blue F3G-A. Copyright © 2008 John Wiley & Sons, Ltd.

The mechanical opening of drainage trenches cannot ensure constant drain line slopes. Therefore vertical bends in the pipelines are being formed. Air accumulates in these bends. Consequently the conductivity of collector drains reduces. The air is carried out by the water flow. However significant air volumes are not removed until the beginning of the dry season. Particularly unfavourable conditions for drainage operation are created when the slope of the collector drains is undulating. For the hydraulic calculation of drain parameters, an estimation of air volumes accumulated in drainage systems at the control time has to be performed. The calculation of the air moving process is necessary during the entire snow melting period. The special hydraulic calculation method is needed for this purpose. The creation and applying of this method is described in the article.

One of the tasks of environmental protection is to achieve good ecological status of water bodies and reduce agricultural non-point pollution. As the drainage outflow may be identified as the leading source of water quality, reduction of nutrient transport through drains is therefore of great importance. The field studies on the impact of lime admixture into trench backfill on the amount of phosphorus contained in drainage outflow were conducted in a site located in south-western Lithuania. Heavy-textured clay loam soils prevailed in the catchment. The site was drained by a composite subsurface drainage system with drain spacing of 16 and 24 m. To improve water permeability, drainage trenches were backfilled with soil mixed with 0.6% CaO. Results of seven-year studies (1999-2005) on water quality are reported in this paper. The significant differences between orthophosphate concentrations in control drainage outflow and the treatments with lime added into the trench backfill were estimated. In water of the control drainage these concentrations were found to be 2.8 times higher. A slightly decreasing trend of total phosphorus (r = 0.49) and orthophosphates (r=0.54) was determined in the stream where drainage water discharged. Annual median phosphorus concentrations have generally remained steady in the outflow of limed drainage treatments. Lime admixture reduces the annual load of total phosphorus and orthophosphate by two and three times respectively, compared with a conventional drainage system. Copyright (c) 2007 John Wiley & Sons, Ltd.

The paper deals with the problem of the redevelopment of derelict buildings and abandoned sites as a complex issue that includes environmental, social and economic aspects. The objective of the research was to suggest a model for determining the rational revitalization of derelict immovable property from the perspective of sustainable development. The authors assume that a multi-criterion analysis is an appropriate technique to use to assure equilibrium among various domains of sustainability. When taking into account the uncertainty of a problem, calculations using the fuzzy version of the TOPSIS method were proposed. The development of a model for determining revitalization priorities of abandoned buildings was based on a case study of derelict rural buildings in Lithuania. A set of indicators was defined and used to perform the multi-criterion analysis of revitalization alternatives of the derelict buildings. Based on results from calculations, scientific recommendations for a rational revitalization of buildings and their sites were prepared.