Thermaltransport phenomenon of submerged arc welding process

U ovom je radu opisan prijelaz topline razmatrajući toplinsko zračenje izvora topline ovalnog oblika i prijenos topline rastaljene pokretne elektrode. Analitičkom se temperaturnom polju približilo ravnim segmentima za ovalni izvor topline s putanjom uzimajući u obzir promjene temperature uzrokovane sljedećim prijelazima (porast temperature zbog izvora topline i rastaljene pokretne elektrode i automatski hlađena područja ranije zagrijana). Točnost rješenja je provjerena usporedbom s eksperimentalnim rezultatima.In present work, thermal transport considering heat radiation by oval heat source shape and heat transfer of molten moving electrode was presented. In present paper, an analytical solution was presented by aggregating temperature increments caused by applying liquid metal and heat radiation of moving electrode. The assumptions for the study were heat source of temperature of applied metal in oval shape and Gaussian distribution of electric heat source. Accuracy of the solution was verified comparing experimental results

Different Vancomycin Immunoassays Contribute to the Variability in Vancomycin Trough Measurements in Neonates

Substantial interassay variability (up to 20%) has been described for vancomycin immunoassays in adults, but the impact of neonatal matrix is difficult to quantify because of blood volume constraints in neonates. However, we provide circumstantial evidence for a similar extent of variability. Using the same vancomycin dosing regimens and confirming similarity in clinical characteristics, vancomycin trough concentrations measured by PETINIA (2011-2012, n = 400) were 20% lower and the mean difference was 1.93 mg/L compared to COBAS (2012-2014, n = 352) measurements. The impact of vancomycin immunoassays in neonatal matrix was hereby suggested, supporting a switch to more advanced techniques (LC-MS/MS)

Topographic inspection as a method of weld joint diagnostic

U radu se demonstrira topografsko ispitivanje u specifičnom kontekstu triju vrsta inspekcijskih metoda zavara od austenitnog nehrđajučeg željeza. Vizualna i metrološka kontrola provedena je tijekom ispitivanja zavarivanja TIG postupkom, primjenom ne-destruktivnih metoda: rendgensko ispitivanje, kompjuterizirana tomografija i profilometrija površine. Rad je reakcija na nedostatak informacija, posebice u području ne-destruktivnih metoda prikladnih za široku primjenu u praksi. U radu se prezentiraju prednosti i nedostaci analiziranih dijagnostičkih metoda i klasifikacija uobičajenih i specifičnih mana zavarenog spoja. Najvažnija neispravnost u praktičnim primjenama kod određivanja pouzdanosti zavarenog spoja su pukotine. Ova vrsta dijagnoze zasnovana je na dobivenim podacima o promatranom anizotropskom i nehomogenom volumenu u dijelu zavara pod utjecajem topline.The paper demonstrates a topographic inspection in the specific context of three kinds of inspection methods of austenitic stainless steel welds. Visual and metrological inspection was analysed during tungsten inert gas (TIG) welding tests, showing the non-destructive techniques: X-ray, computed tomography, and surface profilometry. The article is a response to the lack of information, especially in the area of non-destructive techniques suitable for wide practical application. The Paper presents advantages and drawbacks of the analysed diagnostic methods and a classification of conventional and specific welded joint flaws. The most important defect in practical applications determining reliability of a welded joint is cracks. This kind of diagnostic is based on the obtained information about anisotropic and inhomogeneous volume under consideration in the heat-affected zone of a weld

Thermaltransport phenomenon of submerged arc welding process

U ovom je radu opisan prijelaz topline razmatrajući toplinsko zračenje izvora topline ovalnog oblika i prijenos topline rastaljene pokretne elektrode. Analitičkom se temperaturnom polju približilo ravnim segmentima za ovalni izvor topline s putanjom uzimajući u obzir promjene temperature uzrokovane sljedećim prijelazima (porast temperature zbog izvora topline i rastaljene pokretne elektrode i automatski hlađena područja ranije zagrijana). Točnost rješenja je provjerena usporedbom s eksperimentalnim rezultatima.In present work, thermal transport considering heat radiation by oval heat source shape and heat transfer of molten moving electrode was presented. In present paper, an analytical solution was presented by aggregating temperature increments caused by applying liquid metal and heat radiation of moving electrode. The assumptions for the study were heat source of temperature of applied metal in oval shape and Gaussian distribution of electric heat source. Accuracy of the solution was verified comparing experimental results

Urban Shrinkage in Serbia: The Domination of Economic over Environmental Causes

Although present in Serbia, the phenomenon of urban shrinkage has not been identified as a problem by local decision-makers. The purpose of this study is to present this phenomenon and to show the causes and consequences of urban shrinkage in Serbia. The analysis covers a recent period, 2002-2011, when this process was the most intensive. This study employs the method of grouping towns affected by the shrinkage process. The multi-criteria evaluation method was used to determine the types of towns according to the cause of shrinking, the intensity of the shrinkage factors and the character of the process. In the study of urban shrinkage in the territory of Serbia, environmental factors were considered as one of the causes. Environmental problems are an important factor of urban shrinkage in the developed world. Nevertheless, in Serbia, the economic causes are so dominant that they overpower major environmental issues as potential factors of the shrinking process. Apart from the key factors in this process in most East European and South-East European countries, urban shrinkage in Serbia has its roots in other factors – namely, the political instability caused by inter-ethnic conflicts in the Western Balkans during the 1990s

Central Russia agroecosystem monitoring with CO2 fluxes analysis by eddy covariance method

The eddy covariance (EC) technique as a powerful statistics-based method of measurement and calculation the vertical turbulent fluxes of greenhouses gases within atmospheric boundary layers provides the continuous, long-term flux information integrated at the ecosystem scale. An attractive way to compare the agricultural practices influences on GHG fluxes is to divide a crop area into subplots managed in different ways. The research has been carried out in the Precision Farming Experimental Field of the Russian Timiryazev State Agricultural University (RTSAU, Moscow) in 2013 under the support of RF Government grant # 11.G34.31.0079, EU grant # 603542 LUС4С (7FP) and RF Ministry of education and science grant # 14-120-14-4266-ScSh. Arable Umbric Albeluvisols have around 1% of SOC, 5.4 pH (KCl) and NPK medium-enhanced contents in sandy loam topsoil. The CO2 flux seasonal monitoring has been done by two eddy covariance stations located at the distance of 108 m. The LI-COR instrumental equipment was the same for the both stations. The stations differ only by current crop version: barley or vetch and oats. At both sites, diurnal patterns of NEE among different months were very similar in shape but varied slightly in amplitude. NEE values were about zero during spring time. CO2 fluxes have been intensified after crop emerging from values of 3 to 7 µmol/s∙m2 for emission, and from 5 to 20 µmol/s∙m2 for sink. Stabilization of the fluxes has come at achieving plants height of 10-12 cm. Average NEE was negative only in June and July. Maximum uptake was observed in June with average values about 8 µmol CO2 m−2 s−1. Although different kind of crops were planted on the fields A and B, GPP dynamics was quite similar for both sites: after reaching the peak values at the mid of June, GPP decreased from 4 to 0.5 g C CO2 m-2 d-1 at the end of July. The difference in crops harvesting time that was equal two weeks did not significantly influence the daily GPP patterns. Cumulative assimilation of CO2 at the end of the growing season was about 150 g C m−2 for both sites. So the difference in NEE was the consequence of essentially higher respiration rates in case of vetch and oats (about 350 g C m−2) comparing to barley (250 g C m−2) that needs additional research. The results have shown high daily and seasonal dynamic of CO2 emission too as a result of different and contrasted conditions: crop type, crop development stage, soil moisture and air temperature. Obtained unique for Russian agriculture data are useful for land-use practices environmental assessment, for soil organic carbon dynamics analysis and agroecological evaluation

Urban Shrinkage in Serbia: The Domination of Economic over Environmental Causes

Although present in Serbia, the phenomenon of urban shrinkage has not been identified as a problem by local decision-makers. The purpose of this study is to present this phenomenon and to show the causes and consequences of urban shrinkage in Serbia. The analysis covers a recent period, 2002-2011, when this process was the most intensive. This study employs the method of grouping towns affected by the shrinkage process. The multi-criteria evaluation method was used to determine the types of towns according to the cause of shrinking, the intensity of the shrinkage factors and the character of the process. In the study of urban shrinkage in the territory of Serbia, environmental factors were considered as one of the causes. Environmental problems are an important factor of urban shrinkage in the developed world. Nevertheless, in Serbia, the economic causes are so dominant that they overpower major environmental issues as potential factors of the shrinking process. Apart from the key factors in this process in most East European and South-East European countries, urban shrinkage in Serbia has its roots in other factors – namely, the political instability caused by inter-ethnic conflicts in the Western Balkans during the 1990s

Different vancomycin immuno-assays contribute to the variability in vancomycin trough measurements in neonates

Substantial interassay variability (up to 20%) has been described for vancomycin immunoassays in adults, but the impact of neonatal matrix is difficult to quantify because of blood volume constraints in neonates. However, we provide circumstantial evidence for a similar extent of variability. Using the same vancomycin dosing regimens and confirming similarity in clinical characteristics, vancomycin trough concentrations measured by PETINIA (2011-2012, n = 400) were 20% lower and the mean difference was 1.93 mg/L compared to COBAS (2012-2014, n = 352) measurements. The impact of vancomycin immunoassays in neonatal matrix was hereby suggested, supporting a switch to more advanced techniques (LC-MS/MS).status: publishe

Die "STERNBERG-Originale" der Bayerischen Staatssammlung f\ufcr Pal\ue4ontologie und historische Geologie zu M\ufcnchen

Volume: 12Start Page: 105End Page: 11